this.BX = this.BX || {};
(function (exports) {
  'use strict';

  var version = "5.9.2";

  function ascending (a, b) {
    return a < b ? -1 : a > b ? 1 : a >= b ? 0 : NaN;
  }

  function bisector (compare) {
    if (compare.length === 1) compare = ascendingComparator(compare);
    return {
      left: function left(a, x, lo, hi) {
        if (lo == null) lo = 0;
        if (hi == null) hi = a.length;

        while (lo < hi) {
          var mid = lo + hi >>> 1;
          if (compare(a[mid], x) < 0) lo = mid + 1;else hi = mid;
        }

        return lo;
      },
      right: function right(a, x, lo, hi) {
        if (lo == null) lo = 0;
        if (hi == null) hi = a.length;

        while (lo < hi) {
          var mid = lo + hi >>> 1;
          if (compare(a[mid], x) > 0) hi = mid;else lo = mid + 1;
        }

        return lo;
      }
    };
  }

  function ascendingComparator(f) {
    return function (d, x) {
      return ascending(f(d), x);
    };
  }

  var ascendingBisect = bisector(ascending);
  var bisectRight = ascendingBisect.right;
  var bisectLeft = ascendingBisect.left;

  function pairs (array, f) {
    if (f == null) f = pair;
    var i = 0,
        n = array.length - 1,
        p = array[0],
        pairs = new Array(n < 0 ? 0 : n);

    while (i < n) {
      pairs[i] = f(p, p = array[++i]);
    }

    return pairs;
  }
  function pair(a, b) {
    return [a, b];
  }

  function cross (values0, values1, reduce) {
    var n0 = values0.length,
        n1 = values1.length,
        values = new Array(n0 * n1),
        i0,
        i1,
        i,
        value0;
    if (reduce == null) reduce = pair;

    for (i0 = i = 0; i0 < n0; ++i0) {
      for (value0 = values0[i0], i1 = 0; i1 < n1; ++i1, ++i) {
        values[i] = reduce(value0, values1[i1]);
      }
    }

    return values;
  }

  function descending (a, b) {
    return b < a ? -1 : b > a ? 1 : b >= a ? 0 : NaN;
  }

  function number (x) {
    return x === null ? NaN : +x;
  }

  function variance (values, valueof) {
    var n = values.length,
        m = 0,
        i = -1,
        mean = 0,
        value,
        delta,
        sum = 0;

    if (valueof == null) {
      while (++i < n) {
        if (!isNaN(value = number(values[i]))) {
          delta = value - mean;
          mean += delta / ++m;
          sum += delta * (value - mean);
        }
      }
    } else {
      while (++i < n) {
        if (!isNaN(value = number(valueof(values[i], i, values)))) {
          delta = value - mean;
          mean += delta / ++m;
          sum += delta * (value - mean);
        }
      }
    }

    if (m > 1) return sum / (m - 1);
  }

  function deviation (array, f) {
    var v = variance(array, f);
    return v ? Math.sqrt(v) : v;
  }

  function extent (values, valueof) {
    var n = values.length,
        i = -1,
        value,
        min,
        max;

    if (valueof == null) {
      while (++i < n) {
        // Find the first comparable value.
        if ((value = values[i]) != null && value >= value) {
          min = max = value;

          while (++i < n) {
            // Compare the remaining values.
            if ((value = values[i]) != null) {
              if (min > value) min = value;
              if (max < value) max = value;
            }
          }
        }
      }
    } else {
      while (++i < n) {
        // Find the first comparable value.
        if ((value = valueof(values[i], i, values)) != null && value >= value) {
          min = max = value;

          while (++i < n) {
            // Compare the remaining values.
            if ((value = valueof(values[i], i, values)) != null) {
              if (min > value) min = value;
              if (max < value) max = value;
            }
          }
        }
      }
    }

    return [min, max];
  }

  var array = Array.prototype;
  var slice = array.slice;
  var map = array.map;

  function constant (x) {
    return function () {
      return x;
    };
  }

  function identity (x) {
    return x;
  }

  function sequence (start, stop, step) {
    start = +start, stop = +stop, step = (n = arguments.length) < 2 ? (stop = start, start = 0, 1) : n < 3 ? 1 : +step;
    var i = -1,
        n = Math.max(0, Math.ceil((stop - start) / step)) | 0,
        range = new Array(n);

    while (++i < n) {
      range[i] = start + i * step;
    }

    return range;
  }

  var e10 = Math.sqrt(50),
      e5 = Math.sqrt(10),
      e2 = Math.sqrt(2);
  function ticks (start, stop, count) {
    var reverse,
        i = -1,
        n,
        ticks,
        step;
    stop = +stop, start = +start, count = +count;
    if (start === stop && count > 0) return [start];
    if (reverse = stop < start) n = start, start = stop, stop = n;
    if ((step = tickIncrement(start, stop, count)) === 0 || !isFinite(step)) return [];

    if (step > 0) {
      start = Math.ceil(start / step);
      stop = Math.floor(stop / step);
      ticks = new Array(n = Math.ceil(stop - start + 1));

      while (++i < n) {
        ticks[i] = (start + i) * step;
      }
    } else {
      start = Math.floor(start * step);
      stop = Math.ceil(stop * step);
      ticks = new Array(n = Math.ceil(start - stop + 1));

      while (++i < n) {
        ticks[i] = (start - i) / step;
      }
    }

    if (reverse) ticks.reverse();
    return ticks;
  }
  function tickIncrement(start, stop, count) {
    var step = (stop - start) / Math.max(0, count),
        power = Math.floor(Math.log(step) / Math.LN10),
        error = step / Math.pow(10, power);
    return power >= 0 ? (error >= e10 ? 10 : error >= e5 ? 5 : error >= e2 ? 2 : 1) * Math.pow(10, power) : -Math.pow(10, -power) / (error >= e10 ? 10 : error >= e5 ? 5 : error >= e2 ? 2 : 1);
  }
  function tickStep(start, stop, count) {
    var step0 = Math.abs(stop - start) / Math.max(0, count),
        step1 = Math.pow(10, Math.floor(Math.log(step0) / Math.LN10)),
        error = step0 / step1;
    if (error >= e10) step1 *= 10;else if (error >= e5) step1 *= 5;else if (error >= e2) step1 *= 2;
    return stop < start ? -step1 : step1;
  }

  function thresholdSturges (values) {
    return Math.ceil(Math.log(values.length) / Math.LN2) + 1;
  }

  function histogram () {
    var value = identity,
        domain = extent,
        threshold = thresholdSturges;

    function histogram(data) {
      var i,
          n = data.length,
          x,
          values = new Array(n);

      for (i = 0; i < n; ++i) {
        values[i] = value(data[i], i, data);
      }

      var xz = domain(values),
          x0 = xz[0],
          x1 = xz[1],
          tz = threshold(values, x0, x1); // Convert number of thresholds into uniform thresholds.

      if (!Array.isArray(tz)) {
        tz = tickStep(x0, x1, tz);
        tz = sequence(Math.ceil(x0 / tz) * tz, x1, tz); // exclusive
      } // Remove any thresholds outside the domain.


      var m = tz.length;

      while (tz[0] <= x0) {
        tz.shift(), --m;
      }

      while (tz[m - 1] > x1) {
        tz.pop(), --m;
      }

      var bins = new Array(m + 1),
          bin; // Initialize bins.

      for (i = 0; i <= m; ++i) {
        bin = bins[i] = [];
        bin.x0 = i > 0 ? tz[i - 1] : x0;
        bin.x1 = i < m ? tz[i] : x1;
      } // Assign data to bins by value, ignoring any outside the domain.


      for (i = 0; i < n; ++i) {
        x = values[i];

        if (x0 <= x && x <= x1) {
          bins[bisectRight(tz, x, 0, m)].push(data[i]);
        }
      }

      return bins;
    }

    histogram.value = function (_) {
      return arguments.length ? (value = typeof _ === "function" ? _ : constant(_), histogram) : value;
    };

    histogram.domain = function (_) {
      return arguments.length ? (domain = typeof _ === "function" ? _ : constant([_[0], _[1]]), histogram) : domain;
    };

    histogram.thresholds = function (_) {
      return arguments.length ? (threshold = typeof _ === "function" ? _ : Array.isArray(_) ? constant(slice.call(_)) : constant(_), histogram) : threshold;
    };

    return histogram;
  }

  function threshold (values, p, valueof) {
    if (valueof == null) valueof = number;
    if (!(n = values.length)) return;
    if ((p = +p) <= 0 || n < 2) return +valueof(values[0], 0, values);
    if (p >= 1) return +valueof(values[n - 1], n - 1, values);
    var n,
        i = (n - 1) * p,
        i0 = Math.floor(i),
        value0 = +valueof(values[i0], i0, values),
        value1 = +valueof(values[i0 + 1], i0 + 1, values);
    return value0 + (value1 - value0) * (i - i0);
  }

  function freedmanDiaconis (values, min, max) {
    values = map.call(values, number).sort(ascending);
    return Math.ceil((max - min) / (2 * (threshold(values, 0.75) - threshold(values, 0.25)) * Math.pow(values.length, -1 / 3)));
  }

  function scott (values, min, max) {
    return Math.ceil((max - min) / (3.5 * deviation(values) * Math.pow(values.length, -1 / 3)));
  }

  function max (values, valueof) {
    var n = values.length,
        i = -1,
        value,
        max;

    if (valueof == null) {
      while (++i < n) {
        // Find the first comparable value.
        if ((value = values[i]) != null && value >= value) {
          max = value;

          while (++i < n) {
            // Compare the remaining values.
            if ((value = values[i]) != null && value > max) {
              max = value;
            }
          }
        }
      }
    } else {
      while (++i < n) {
        // Find the first comparable value.
        if ((value = valueof(values[i], i, values)) != null && value >= value) {
          max = value;

          while (++i < n) {
            // Compare the remaining values.
            if ((value = valueof(values[i], i, values)) != null && value > max) {
              max = value;
            }
          }
        }
      }
    }

    return max;
  }

  function mean (values, valueof) {
    var n = values.length,
        m = n,
        i = -1,
        value,
        sum = 0;

    if (valueof == null) {
      while (++i < n) {
        if (!isNaN(value = number(values[i]))) sum += value;else --m;
      }
    } else {
      while (++i < n) {
        if (!isNaN(value = number(valueof(values[i], i, values)))) sum += value;else --m;
      }
    }

    if (m) return sum / m;
  }

  function median (values, valueof) {
    var n = values.length,
        i = -1,
        value,
        numbers = [];

    if (valueof == null) {
      while (++i < n) {
        if (!isNaN(value = number(values[i]))) {
          numbers.push(value);
        }
      }
    } else {
      while (++i < n) {
        if (!isNaN(value = number(valueof(values[i], i, values)))) {
          numbers.push(value);
        }
      }
    }

    return threshold(numbers.sort(ascending), 0.5);
  }

  function merge (arrays) {
    var n = arrays.length,
        m,
        i = -1,
        j = 0,
        merged,
        array;

    while (++i < n) {
      j += arrays[i].length;
    }

    merged = new Array(j);

    while (--n >= 0) {
      array = arrays[n];
      m = array.length;

      while (--m >= 0) {
        merged[--j] = array[m];
      }
    }

    return merged;
  }

  function min (values, valueof) {
    var n = values.length,
        i = -1,
        value,
        min;

    if (valueof == null) {
      while (++i < n) {
        // Find the first comparable value.
        if ((value = values[i]) != null && value >= value) {
          min = value;

          while (++i < n) {
            // Compare the remaining values.
            if ((value = values[i]) != null && min > value) {
              min = value;
            }
          }
        }
      }
    } else {
      while (++i < n) {
        // Find the first comparable value.
        if ((value = valueof(values[i], i, values)) != null && value >= value) {
          min = value;

          while (++i < n) {
            // Compare the remaining values.
            if ((value = valueof(values[i], i, values)) != null && min > value) {
              min = value;
            }
          }
        }
      }
    }

    return min;
  }

  function permute (array, indexes) {
    var i = indexes.length,
        permutes = new Array(i);

    while (i--) {
      permutes[i] = array[indexes[i]];
    }

    return permutes;
  }

  function scan (values, compare) {
    if (!(n = values.length)) return;
    var n,
        i = 0,
        j = 0,
        xi,
        xj = values[j];
    if (compare == null) compare = ascending;

    while (++i < n) {
      if (compare(xi = values[i], xj) < 0 || compare(xj, xj) !== 0) {
        xj = xi, j = i;
      }
    }

    if (compare(xj, xj) === 0) return j;
  }

  function shuffle (array, i0, i1) {
    var m = (i1 == null ? array.length : i1) - (i0 = i0 == null ? 0 : +i0),
        t,
        i;

    while (m) {
      i = Math.random() * m-- | 0;
      t = array[m + i0];
      array[m + i0] = array[i + i0];
      array[i + i0] = t;
    }

    return array;
  }

  function sum (values, valueof) {
    var n = values.length,
        i = -1,
        value,
        sum = 0;

    if (valueof == null) {
      while (++i < n) {
        if (value = +values[i]) sum += value; // Note: zero and null are equivalent.
      }
    } else {
      while (++i < n) {
        if (value = +valueof(values[i], i, values)) sum += value;
      }
    }

    return sum;
  }

  function transpose (matrix) {
    if (!(n = matrix.length)) return [];

    for (var i = -1, m = min(matrix, length), transpose = new Array(m); ++i < m;) {
      for (var j = -1, n, row = transpose[i] = new Array(n); ++j < n;) {
        row[j] = matrix[j][i];
      }
    }

    return transpose;
  }

  function length(d) {
    return d.length;
  }

  function zip () {
    return transpose(arguments);
  }

  var slice$1 = Array.prototype.slice;

  function identity$1 (x) {
    return x;
  }

  var top = 1,
      right = 2,
      bottom = 3,
      left = 4,
      epsilon = 1e-6;

  function translateX(x) {
    return "translate(" + (x + 0.5) + ",0)";
  }

  function translateY(y) {
    return "translate(0," + (y + 0.5) + ")";
  }

  function number$1(scale) {
    return function (d) {
      return +scale(d);
    };
  }

  function center(scale) {
    var offset = Math.max(0, scale.bandwidth() - 1) / 2; // Adjust for 0.5px offset.

    if (scale.round()) offset = Math.round(offset);
    return function (d) {
      return +scale(d) + offset;
    };
  }

  function entering() {
    return !this.__axis;
  }

  function axis(orient, scale) {
    var tickArguments = [],
        tickValues = null,
        tickFormat = null,
        tickSizeInner = 6,
        tickSizeOuter = 6,
        tickPadding = 3,
        k = orient === top || orient === left ? -1 : 1,
        x = orient === left || orient === right ? "x" : "y",
        transform = orient === top || orient === bottom ? translateX : translateY;

    function axis(context) {
      var values = tickValues == null ? scale.ticks ? scale.ticks.apply(scale, tickArguments) : scale.domain() : tickValues,
          format = tickFormat == null ? scale.tickFormat ? scale.tickFormat.apply(scale, tickArguments) : identity$1 : tickFormat,
          spacing = Math.max(tickSizeInner, 0) + tickPadding,
          range = scale.range(),
          range0 = +range[0] + 0.5,
          range1 = +range[range.length - 1] + 0.5,
          position = (scale.bandwidth ? center : number$1)(scale.copy()),
          selection = context.selection ? context.selection() : context,
          path = selection.selectAll(".domain").data([null]),
          tick = selection.selectAll(".tick").data(values, scale).order(),
          tickExit = tick.exit(),
          tickEnter = tick.enter().append("g").attr("class", "tick"),
          line = tick.select("line"),
          text = tick.select("text");
      path = path.merge(path.enter().insert("path", ".tick").attr("class", "domain").attr("stroke", "currentColor"));
      tick = tick.merge(tickEnter);
      line = line.merge(tickEnter.append("line").attr("stroke", "currentColor").attr(x + "2", k * tickSizeInner));
      text = text.merge(tickEnter.append("text").attr("fill", "currentColor").attr(x, k * spacing).attr("dy", orient === top ? "0em" : orient === bottom ? "0.71em" : "0.32em"));

      if (context !== selection) {
        path = path.transition(context);
        tick = tick.transition(context);
        line = line.transition(context);
        text = text.transition(context);
        tickExit = tickExit.transition(context).attr("opacity", epsilon).attr("transform", function (d) {
          return isFinite(d = position(d)) ? transform(d) : this.getAttribute("transform");
        });
        tickEnter.attr("opacity", epsilon).attr("transform", function (d) {
          var p = this.parentNode.__axis;
          return transform(p && isFinite(p = p(d)) ? p : position(d));
        });
      }

      tickExit.remove();
      path.attr("d", orient === left || orient == right ? tickSizeOuter ? "M" + k * tickSizeOuter + "," + range0 + "H0.5V" + range1 + "H" + k * tickSizeOuter : "M0.5," + range0 + "V" + range1 : tickSizeOuter ? "M" + range0 + "," + k * tickSizeOuter + "V0.5H" + range1 + "V" + k * tickSizeOuter : "M" + range0 + ",0.5H" + range1);
      tick.attr("opacity", 1).attr("transform", function (d) {
        return transform(position(d));
      });
      line.attr(x + "2", k * tickSizeInner);
      text.attr(x, k * spacing).text(format);
      selection.filter(entering).attr("fill", "none").attr("font-size", 10).attr("font-family", "sans-serif").attr("text-anchor", orient === right ? "start" : orient === left ? "end" : "middle");
      selection.each(function () {
        this.__axis = position;
      });
    }

    axis.scale = function (_) {
      return arguments.length ? (scale = _, axis) : scale;
    };

    axis.ticks = function () {
      return tickArguments = slice$1.call(arguments), axis;
    };

    axis.tickArguments = function (_) {
      return arguments.length ? (tickArguments = _ == null ? [] : slice$1.call(_), axis) : tickArguments.slice();
    };

    axis.tickValues = function (_) {
      return arguments.length ? (tickValues = _ == null ? null : slice$1.call(_), axis) : tickValues && tickValues.slice();
    };

    axis.tickFormat = function (_) {
      return arguments.length ? (tickFormat = _, axis) : tickFormat;
    };

    axis.tickSize = function (_) {
      return arguments.length ? (tickSizeInner = tickSizeOuter = +_, axis) : tickSizeInner;
    };

    axis.tickSizeInner = function (_) {
      return arguments.length ? (tickSizeInner = +_, axis) : tickSizeInner;
    };

    axis.tickSizeOuter = function (_) {
      return arguments.length ? (tickSizeOuter = +_, axis) : tickSizeOuter;
    };

    axis.tickPadding = function (_) {
      return arguments.length ? (tickPadding = +_, axis) : tickPadding;
    };

    return axis;
  }

  function axisTop(scale) {
    return axis(top, scale);
  }
  function axisRight(scale) {
    return axis(right, scale);
  }
  function axisBottom(scale) {
    return axis(bottom, scale);
  }
  function axisLeft(scale) {
    return axis(left, scale);
  }

  var noop = {
    value: function value() {}
  };

  function dispatch() {
    for (var i = 0, n = arguments.length, _ = {}, t; i < n; ++i) {
      if (!(t = arguments[i] + "") || t in _) throw new Error("illegal type: " + t);
      _[t] = [];
    }

    return new Dispatch(_);
  }

  function Dispatch(_) {
    this._ = _;
  }

  function parseTypenames(typenames, types) {
    return typenames.trim().split(/^|\s+/).map(function (t) {
      var name = "",
          i = t.indexOf(".");
      if (i >= 0) name = t.slice(i + 1), t = t.slice(0, i);
      if (t && !types.hasOwnProperty(t)) throw new Error("unknown type: " + t);
      return {
        type: t,
        name: name
      };
    });
  }

  Dispatch.prototype = dispatch.prototype = {
    constructor: Dispatch,
    on: function on(typename, callback) {
      var _ = this._,
          T = parseTypenames(typename + "", _),
          t,
          i = -1,
          n = T.length; // If no callback was specified, return the callback of the given type and name.

      if (arguments.length < 2) {
        while (++i < n) {
          if ((t = (typename = T[i]).type) && (t = get(_[t], typename.name))) return t;
        }

        return;
      } // If a type was specified, set the callback for the given type and name.
      // Otherwise, if a null callback was specified, remove callbacks of the given name.


      if (callback != null && typeof callback !== "function") throw new Error("invalid callback: " + callback);

      while (++i < n) {
        if (t = (typename = T[i]).type) _[t] = set(_[t], typename.name, callback);else if (callback == null) for (t in _) {
          _[t] = set(_[t], typename.name, null);
        }
      }

      return this;
    },
    copy: function copy() {
      var copy = {},
          _ = this._;

      for (var t in _) {
        copy[t] = _[t].slice();
      }

      return new Dispatch(copy);
    },
    call: function call(type, that) {
      if ((n = arguments.length - 2) > 0) for (var args = new Array(n), i = 0, n, t; i < n; ++i) {
        args[i] = arguments[i + 2];
      }
      if (!this._.hasOwnProperty(type)) throw new Error("unknown type: " + type);

      for (t = this._[type], i = 0, n = t.length; i < n; ++i) {
        t[i].value.apply(that, args);
      }
    },
    apply: function apply(type, that, args) {
      if (!this._.hasOwnProperty(type)) throw new Error("unknown type: " + type);

      for (var t = this._[type], i = 0, n = t.length; i < n; ++i) {
        t[i].value.apply(that, args);
      }
    }
  };

  function get(type, name) {
    for (var i = 0, n = type.length, c; i < n; ++i) {
      if ((c = type[i]).name === name) {
        return c.value;
      }
    }
  }

  function set(type, name, callback) {
    for (var i = 0, n = type.length; i < n; ++i) {
      if (type[i].name === name) {
        type[i] = noop, type = type.slice(0, i).concat(type.slice(i + 1));
        break;
      }
    }

    if (callback != null) type.push({
      name: name,
      value: callback
    });
    return type;
  }

  var xhtml = "http://www.w3.org/1999/xhtml";
  var namespaces = {
    svg: "http://www.w3.org/2000/svg",
    xhtml: xhtml,
    xlink: "http://www.w3.org/1999/xlink",
    xml: "http://www.w3.org/XML/1998/namespace",
    xmlns: "http://www.w3.org/2000/xmlns/"
  };

  function namespace (name) {
    var prefix = name += "",
        i = prefix.indexOf(":");
    if (i >= 0 && (prefix = name.slice(0, i)) !== "xmlns") name = name.slice(i + 1);
    return namespaces.hasOwnProperty(prefix) ? {
      space: namespaces[prefix],
      local: name
    } : name;
  }

  function creatorInherit(name) {
    return function () {
      var document = this.ownerDocument,
          uri = this.namespaceURI;
      return uri === xhtml && document.documentElement.namespaceURI === xhtml ? document.createElement(name) : document.createElementNS(uri, name);
    };
  }

  function creatorFixed(fullname) {
    return function () {
      return this.ownerDocument.createElementNS(fullname.space, fullname.local);
    };
  }

  function creator (name) {
    var fullname = namespace(name);
    return (fullname.local ? creatorFixed : creatorInherit)(fullname);
  }

  function none() {}

  function selector (selector) {
    return selector == null ? none : function () {
      return this.querySelector(selector);
    };
  }

  function selection_select (select) {
    if (typeof select !== "function") select = selector(select);

    for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, subgroup = subgroups[j] = new Array(n), node, subnode, i = 0; i < n; ++i) {
        if ((node = group[i]) && (subnode = select.call(node, node.__data__, i, group))) {
          if ("__data__" in node) subnode.__data__ = node.__data__;
          subgroup[i] = subnode;
        }
      }
    }

    return new Selection(subgroups, this._parents);
  }

  function empty() {
    return [];
  }

  function selectorAll (selector) {
    return selector == null ? empty : function () {
      return this.querySelectorAll(selector);
    };
  }

  function selection_selectAll (select) {
    if (typeof select !== "function") select = selectorAll(select);

    for (var groups = this._groups, m = groups.length, subgroups = [], parents = [], j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
        if (node = group[i]) {
          subgroups.push(select.call(node, node.__data__, i, group));
          parents.push(node);
        }
      }
    }

    return new Selection(subgroups, parents);
  }

  function matcher (selector) {
    return function () {
      return this.matches(selector);
    };
  }

  function selection_filter (match) {
    if (typeof match !== "function") match = matcher(match);

    for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, subgroup = subgroups[j] = [], node, i = 0; i < n; ++i) {
        if ((node = group[i]) && match.call(node, node.__data__, i, group)) {
          subgroup.push(node);
        }
      }
    }

    return new Selection(subgroups, this._parents);
  }

  function sparse (update) {
    return new Array(update.length);
  }

  function selection_enter () {
    return new Selection(this._enter || this._groups.map(sparse), this._parents);
  }
  function EnterNode(parent, datum) {
    this.ownerDocument = parent.ownerDocument;
    this.namespaceURI = parent.namespaceURI;
    this._next = null;
    this._parent = parent;
    this.__data__ = datum;
  }
  EnterNode.prototype = {
    constructor: EnterNode,
    appendChild: function appendChild(child) {
      return this._parent.insertBefore(child, this._next);
    },
    insertBefore: function insertBefore(child, next) {
      return this._parent.insertBefore(child, next);
    },
    querySelector: function querySelector(selector) {
      return this._parent.querySelector(selector);
    },
    querySelectorAll: function querySelectorAll(selector) {
      return this._parent.querySelectorAll(selector);
    }
  };

  function constant$1 (x) {
    return function () {
      return x;
    };
  }

  var keyPrefix = "$"; // Protect against keys like “__proto__”.

  function bindIndex(parent, group, enter, update, exit, data) {
    var i = 0,
        node,
        groupLength = group.length,
        dataLength = data.length; // Put any non-null nodes that fit into update.
    // Put any null nodes into enter.
    // Put any remaining data into enter.

    for (; i < dataLength; ++i) {
      if (node = group[i]) {
        node.__data__ = data[i];
        update[i] = node;
      } else {
        enter[i] = new EnterNode(parent, data[i]);
      }
    } // Put any non-null nodes that don’t fit into exit.


    for (; i < groupLength; ++i) {
      if (node = group[i]) {
        exit[i] = node;
      }
    }
  }

  function bindKey(parent, group, enter, update, exit, data, key) {
    var i,
        node,
        nodeByKeyValue = {},
        groupLength = group.length,
        dataLength = data.length,
        keyValues = new Array(groupLength),
        keyValue; // Compute the key for each node.
    // If multiple nodes have the same key, the duplicates are added to exit.

    for (i = 0; i < groupLength; ++i) {
      if (node = group[i]) {
        keyValues[i] = keyValue = keyPrefix + key.call(node, node.__data__, i, group);

        if (keyValue in nodeByKeyValue) {
          exit[i] = node;
        } else {
          nodeByKeyValue[keyValue] = node;
        }
      }
    } // Compute the key for each datum.
    // If there a node associated with this key, join and add it to update.
    // If there is not (or the key is a duplicate), add it to enter.


    for (i = 0; i < dataLength; ++i) {
      keyValue = keyPrefix + key.call(parent, data[i], i, data);

      if (node = nodeByKeyValue[keyValue]) {
        update[i] = node;
        node.__data__ = data[i];
        nodeByKeyValue[keyValue] = null;
      } else {
        enter[i] = new EnterNode(parent, data[i]);
      }
    } // Add any remaining nodes that were not bound to data to exit.


    for (i = 0; i < groupLength; ++i) {
      if ((node = group[i]) && nodeByKeyValue[keyValues[i]] === node) {
        exit[i] = node;
      }
    }
  }

  function selection_data (value, key) {
    if (!value) {
      data = new Array(this.size()), j = -1;
      this.each(function (d) {
        data[++j] = d;
      });
      return data;
    }

    var bind = key ? bindKey : bindIndex,
        parents = this._parents,
        groups = this._groups;
    if (typeof value !== "function") value = constant$1(value);

    for (var m = groups.length, update = new Array(m), enter = new Array(m), exit = new Array(m), j = 0; j < m; ++j) {
      var parent = parents[j],
          group = groups[j],
          groupLength = group.length,
          data = value.call(parent, parent && parent.__data__, j, parents),
          dataLength = data.length,
          enterGroup = enter[j] = new Array(dataLength),
          updateGroup = update[j] = new Array(dataLength),
          exitGroup = exit[j] = new Array(groupLength);
      bind(parent, group, enterGroup, updateGroup, exitGroup, data, key); // Now connect the enter nodes to their following update node, such that
      // appendChild can insert the materialized enter node before this node,
      // rather than at the end of the parent node.

      for (var i0 = 0, i1 = 0, previous, next; i0 < dataLength; ++i0) {
        if (previous = enterGroup[i0]) {
          if (i0 >= i1) i1 = i0 + 1;

          while (!(next = updateGroup[i1]) && ++i1 < dataLength) {
          }

          previous._next = next || null;
        }
      }
    }

    update = new Selection(update, parents);
    update._enter = enter;
    update._exit = exit;
    return update;
  }

  function selection_exit () {
    return new Selection(this._exit || this._groups.map(sparse), this._parents);
  }

  function selection_join (onenter, onupdate, onexit) {
    var enter = this.enter(),
        update = this,
        exit = this.exit();
    enter = typeof onenter === "function" ? onenter(enter) : enter.append(onenter + "");
    if (onupdate != null) update = onupdate(update);
    if (onexit == null) exit.remove();else onexit(exit);
    return enter && update ? enter.merge(update).order() : update;
  }

  function selection_merge (selection$$1) {
    for (var groups0 = this._groups, groups1 = selection$$1._groups, m0 = groups0.length, m1 = groups1.length, m = Math.min(m0, m1), merges = new Array(m0), j = 0; j < m; ++j) {
      for (var group0 = groups0[j], group1 = groups1[j], n = group0.length, merge = merges[j] = new Array(n), node, i = 0; i < n; ++i) {
        if (node = group0[i] || group1[i]) {
          merge[i] = node;
        }
      }
    }

    for (; j < m0; ++j) {
      merges[j] = groups0[j];
    }

    return new Selection(merges, this._parents);
  }

  function selection_order () {
    for (var groups = this._groups, j = -1, m = groups.length; ++j < m;) {
      for (var group = groups[j], i = group.length - 1, next = group[i], node; --i >= 0;) {
        if (node = group[i]) {
          if (next && node.compareDocumentPosition(next) ^ 4) next.parentNode.insertBefore(node, next);
          next = node;
        }
      }
    }

    return this;
  }

  function selection_sort (compare) {
    if (!compare) compare = ascending$1;

    function compareNode(a, b) {
      return a && b ? compare(a.__data__, b.__data__) : !a - !b;
    }

    for (var groups = this._groups, m = groups.length, sortgroups = new Array(m), j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, sortgroup = sortgroups[j] = new Array(n), node, i = 0; i < n; ++i) {
        if (node = group[i]) {
          sortgroup[i] = node;
        }
      }

      sortgroup.sort(compareNode);
    }

    return new Selection(sortgroups, this._parents).order();
  }

  function ascending$1(a, b) {
    return a < b ? -1 : a > b ? 1 : a >= b ? 0 : NaN;
  }

  function selection_call () {
    var callback = arguments[0];
    arguments[0] = this;
    callback.apply(null, arguments);
    return this;
  }

  function selection_nodes () {
    var nodes = new Array(this.size()),
        i = -1;
    this.each(function () {
      nodes[++i] = this;
    });
    return nodes;
  }

  function selection_node () {
    for (var groups = this._groups, j = 0, m = groups.length; j < m; ++j) {
      for (var group = groups[j], i = 0, n = group.length; i < n; ++i) {
        var node = group[i];
        if (node) return node;
      }
    }

    return null;
  }

  function selection_size () {
    var size = 0;
    this.each(function () {
      ++size;
    });
    return size;
  }

  function selection_empty () {
    return !this.node();
  }

  function selection_each (callback) {
    for (var groups = this._groups, j = 0, m = groups.length; j < m; ++j) {
      for (var group = groups[j], i = 0, n = group.length, node; i < n; ++i) {
        if (node = group[i]) callback.call(node, node.__data__, i, group);
      }
    }

    return this;
  }

  function attrRemove(name) {
    return function () {
      this.removeAttribute(name);
    };
  }

  function attrRemoveNS(fullname) {
    return function () {
      this.removeAttributeNS(fullname.space, fullname.local);
    };
  }

  function attrConstant(name, value) {
    return function () {
      this.setAttribute(name, value);
    };
  }

  function attrConstantNS(fullname, value) {
    return function () {
      this.setAttributeNS(fullname.space, fullname.local, value);
    };
  }

  function attrFunction(name, value) {
    return function () {
      var v = value.apply(this, arguments);
      if (v == null) this.removeAttribute(name);else this.setAttribute(name, v);
    };
  }

  function attrFunctionNS(fullname, value) {
    return function () {
      var v = value.apply(this, arguments);
      if (v == null) this.removeAttributeNS(fullname.space, fullname.local);else this.setAttributeNS(fullname.space, fullname.local, v);
    };
  }

  function selection_attr (name, value) {
    var fullname = namespace(name);

    if (arguments.length < 2) {
      var node = this.node();
      return fullname.local ? node.getAttributeNS(fullname.space, fullname.local) : node.getAttribute(fullname);
    }

    return this.each((value == null ? fullname.local ? attrRemoveNS : attrRemove : typeof value === "function" ? fullname.local ? attrFunctionNS : attrFunction : fullname.local ? attrConstantNS : attrConstant)(fullname, value));
  }

  function defaultView (node) {
    return node.ownerDocument && node.ownerDocument.defaultView || // node is a Node
    node.document && node // node is a Window
    || node.defaultView; // node is a Document
  }

  function styleRemove(name) {
    return function () {
      this.style.removeProperty(name);
    };
  }

  function styleConstant(name, value, priority) {
    return function () {
      this.style.setProperty(name, value, priority);
    };
  }

  function styleFunction(name, value, priority) {
    return function () {
      var v = value.apply(this, arguments);
      if (v == null) this.style.removeProperty(name);else this.style.setProperty(name, v, priority);
    };
  }

  function selection_style (name, value, priority) {
    return arguments.length > 1 ? this.each((value == null ? styleRemove : typeof value === "function" ? styleFunction : styleConstant)(name, value, priority == null ? "" : priority)) : styleValue(this.node(), name);
  }
  function styleValue(node, name) {
    return node.style.getPropertyValue(name) || defaultView(node).getComputedStyle(node, null).getPropertyValue(name);
  }

  function propertyRemove(name) {
    return function () {
      delete this[name];
    };
  }

  function propertyConstant(name, value) {
    return function () {
      this[name] = value;
    };
  }

  function propertyFunction(name, value) {
    return function () {
      var v = value.apply(this, arguments);
      if (v == null) delete this[name];else this[name] = v;
    };
  }

  function selection_property (name, value) {
    return arguments.length > 1 ? this.each((value == null ? propertyRemove : typeof value === "function" ? propertyFunction : propertyConstant)(name, value)) : this.node()[name];
  }

  function classArray(string) {
    return string.trim().split(/^|\s+/);
  }

  function classList(node) {
    return node.classList || new ClassList(node);
  }

  function ClassList(node) {
    this._node = node;
    this._names = classArray(node.getAttribute("class") || "");
  }

  ClassList.prototype = {
    add: function add(name) {
      var i = this._names.indexOf(name);

      if (i < 0) {
        this._names.push(name);

        this._node.setAttribute("class", this._names.join(" "));
      }
    },
    remove: function remove(name) {
      var i = this._names.indexOf(name);

      if (i >= 0) {
        this._names.splice(i, 1);

        this._node.setAttribute("class", this._names.join(" "));
      }
    },
    contains: function contains(name) {
      return this._names.indexOf(name) >= 0;
    }
  };

  function classedAdd(node, names) {
    var list = classList(node),
        i = -1,
        n = names.length;

    while (++i < n) {
      list.add(names[i]);
    }
  }

  function classedRemove(node, names) {
    var list = classList(node),
        i = -1,
        n = names.length;

    while (++i < n) {
      list.remove(names[i]);
    }
  }

  function classedTrue(names) {
    return function () {
      classedAdd(this, names);
    };
  }

  function classedFalse(names) {
    return function () {
      classedRemove(this, names);
    };
  }

  function classedFunction(names, value) {
    return function () {
      (value.apply(this, arguments) ? classedAdd : classedRemove)(this, names);
    };
  }

  function selection_classed (name, value) {
    var names = classArray(name + "");

    if (arguments.length < 2) {
      var list = classList(this.node()),
          i = -1,
          n = names.length;

      while (++i < n) {
        if (!list.contains(names[i])) return false;
      }

      return true;
    }

    return this.each((typeof value === "function" ? classedFunction : value ? classedTrue : classedFalse)(names, value));
  }

  function textRemove() {
    this.textContent = "";
  }

  function textConstant(value) {
    return function () {
      this.textContent = value;
    };
  }

  function textFunction(value) {
    return function () {
      var v = value.apply(this, arguments);
      this.textContent = v == null ? "" : v;
    };
  }

  function selection_text (value) {
    return arguments.length ? this.each(value == null ? textRemove : (typeof value === "function" ? textFunction : textConstant)(value)) : this.node().textContent;
  }

  function htmlRemove() {
    this.innerHTML = "";
  }

  function htmlConstant(value) {
    return function () {
      this.innerHTML = value;
    };
  }

  function htmlFunction(value) {
    return function () {
      var v = value.apply(this, arguments);
      this.innerHTML = v == null ? "" : v;
    };
  }

  function selection_html (value) {
    return arguments.length ? this.each(value == null ? htmlRemove : (typeof value === "function" ? htmlFunction : htmlConstant)(value)) : this.node().innerHTML;
  }

  function raise() {
    if (this.nextSibling) this.parentNode.appendChild(this);
  }

  function selection_raise () {
    return this.each(raise);
  }

  function lower() {
    if (this.previousSibling) this.parentNode.insertBefore(this, this.parentNode.firstChild);
  }

  function selection_lower () {
    return this.each(lower);
  }

  function selection_append (name) {
    var create = typeof name === "function" ? name : creator(name);
    return this.select(function () {
      return this.appendChild(create.apply(this, arguments));
    });
  }

  function constantNull() {
    return null;
  }

  function selection_insert (name, before) {
    var create = typeof name === "function" ? name : creator(name),
        select = before == null ? constantNull : typeof before === "function" ? before : selector(before);
    return this.select(function () {
      return this.insertBefore(create.apply(this, arguments), select.apply(this, arguments) || null);
    });
  }

  function remove() {
    var parent = this.parentNode;
    if (parent) parent.removeChild(this);
  }

  function selection_remove () {
    return this.each(remove);
  }

  function selection_cloneShallow() {
    return this.parentNode.insertBefore(this.cloneNode(false), this.nextSibling);
  }

  function selection_cloneDeep() {
    return this.parentNode.insertBefore(this.cloneNode(true), this.nextSibling);
  }

  function selection_clone (deep) {
    return this.select(deep ? selection_cloneDeep : selection_cloneShallow);
  }

  function selection_datum (value) {
    return arguments.length ? this.property("__data__", value) : this.node().__data__;
  }

  var filterEvents = {};
  exports.event = null;

  if (typeof document !== "undefined") {
    var element = document.documentElement;

    if (!("onmouseenter" in element)) {
      filterEvents = {
        mouseenter: "mouseover",
        mouseleave: "mouseout"
      };
    }
  }

  function filterContextListener(listener, index, group) {
    listener = contextListener(listener, index, group);
    return function (event) {
      var related = event.relatedTarget;

      if (!related || related !== this && !(related.compareDocumentPosition(this) & 8)) {
        listener.call(this, event);
      }
    };
  }

  function contextListener(listener, index, group) {
    return function (event1) {
      var event0 = exports.event; // Events can be reentrant (e.g., focus).

      exports.event = event1;

      try {
        listener.call(this, this.__data__, index, group);
      } finally {
        exports.event = event0;
      }
    };
  }

  function parseTypenames$1(typenames) {
    return typenames.trim().split(/^|\s+/).map(function (t) {
      var name = "",
          i = t.indexOf(".");
      if (i >= 0) name = t.slice(i + 1), t = t.slice(0, i);
      return {
        type: t,
        name: name
      };
    });
  }

  function onRemove(typename) {
    return function () {
      var on = this.__on;
      if (!on) return;

      for (var j = 0, i = -1, m = on.length, o; j < m; ++j) {
        if (o = on[j], (!typename.type || o.type === typename.type) && o.name === typename.name) {
          this.removeEventListener(o.type, o.listener, o.capture);
        } else {
          on[++i] = o;
        }
      }

      if (++i) on.length = i;else delete this.__on;
    };
  }

  function onAdd(typename, value, capture) {
    var wrap = filterEvents.hasOwnProperty(typename.type) ? filterContextListener : contextListener;
    return function (d, i, group) {
      var on = this.__on,
          o,
          listener = wrap(value, i, group);
      if (on) for (var j = 0, m = on.length; j < m; ++j) {
        if ((o = on[j]).type === typename.type && o.name === typename.name) {
          this.removeEventListener(o.type, o.listener, o.capture);
          this.addEventListener(o.type, o.listener = listener, o.capture = capture);
          o.value = value;
          return;
        }
      }
      this.addEventListener(typename.type, listener, capture);
      o = {
        type: typename.type,
        name: typename.name,
        value: value,
        listener: listener,
        capture: capture
      };
      if (!on) this.__on = [o];else on.push(o);
    };
  }

  function selection_on (typename, value, capture) {
    var typenames = parseTypenames$1(typename + ""),
        i,
        n = typenames.length,
        t;

    if (arguments.length < 2) {
      var on = this.node().__on;

      if (on) for (var j = 0, m = on.length, o; j < m; ++j) {
        for (i = 0, o = on[j]; i < n; ++i) {
          if ((t = typenames[i]).type === o.type && t.name === o.name) {
            return o.value;
          }
        }
      }
      return;
    }

    on = value ? onAdd : onRemove;
    if (capture == null) capture = false;

    for (i = 0; i < n; ++i) {
      this.each(on(typenames[i], value, capture));
    }

    return this;
  }
  function customEvent(event1, listener, that, args) {
    var event0 = exports.event;
    event1.sourceEvent = exports.event;
    exports.event = event1;

    try {
      return listener.apply(that, args);
    } finally {
      exports.event = event0;
    }
  }

  function dispatchEvent(node, type, params) {
    var window = defaultView(node),
        event = window.CustomEvent;

    if (typeof event === "function") {
      event = new event(type, params);
    } else {
      event = window.document.createEvent("Event");
      if (params) event.initEvent(type, params.bubbles, params.cancelable), event.detail = params.detail;else event.initEvent(type, false, false);
    }

    node.dispatchEvent(event);
  }

  function dispatchConstant(type, params) {
    return function () {
      return dispatchEvent(this, type, params);
    };
  }

  function dispatchFunction(type, params) {
    return function () {
      return dispatchEvent(this, type, params.apply(this, arguments));
    };
  }

  function selection_dispatch (type, params) {
    return this.each((typeof params === "function" ? dispatchFunction : dispatchConstant)(type, params));
  }

  var root = [null];
  function Selection(groups, parents) {
    this._groups = groups;
    this._parents = parents;
  }

  function selection() {
    return new Selection([[document.documentElement]], root);
  }

  Selection.prototype = selection.prototype = {
    constructor: Selection,
    select: selection_select,
    selectAll: selection_selectAll,
    filter: selection_filter,
    data: selection_data,
    enter: selection_enter,
    exit: selection_exit,
    join: selection_join,
    merge: selection_merge,
    order: selection_order,
    sort: selection_sort,
    call: selection_call,
    nodes: selection_nodes,
    node: selection_node,
    size: selection_size,
    empty: selection_empty,
    each: selection_each,
    attr: selection_attr,
    style: selection_style,
    property: selection_property,
    classed: selection_classed,
    text: selection_text,
    html: selection_html,
    raise: selection_raise,
    lower: selection_lower,
    append: selection_append,
    insert: selection_insert,
    remove: selection_remove,
    clone: selection_clone,
    datum: selection_datum,
    on: selection_on,
    dispatch: selection_dispatch
  };

  function select (selector) {
    return typeof selector === "string" ? new Selection([[document.querySelector(selector)]], [document.documentElement]) : new Selection([[selector]], root);
  }

  function create (name) {
    return select(creator(name).call(document.documentElement));
  }

  var nextId = 0;
  function local() {
    return new Local();
  }

  function Local() {
    this._ = "@" + (++nextId).toString(36);
  }

  Local.prototype = local.prototype = {
    constructor: Local,
    get: function get(node) {
      var id = this._;

      while (!(id in node)) {
        if (!(node = node.parentNode)) return;
      }

      return node[id];
    },
    set: function set(node, value) {
      return node[this._] = value;
    },
    remove: function remove(node) {
      return this._ in node && delete node[this._];
    },
    toString: function toString() {
      return this._;
    }
  };

  function sourceEvent () {
    var current = exports.event,
        source;

    while (source = current.sourceEvent) {
      current = source;
    }

    return current;
  }

  function point (node, event) {
    var svg = node.ownerSVGElement || node;

    if (svg.createSVGPoint) {
      var point = svg.createSVGPoint();
      point.x = event.clientX, point.y = event.clientY;
      point = point.matrixTransform(node.getScreenCTM().inverse());
      return [point.x, point.y];
    }

    var rect = node.getBoundingClientRect();
    return [event.clientX - rect.left - node.clientLeft, event.clientY - rect.top - node.clientTop];
  }

  function mouse (node) {
    var event = sourceEvent();
    if (event.changedTouches) event = event.changedTouches[0];
    return point(node, event);
  }

  function selectAll (selector) {
    return typeof selector === "string" ? new Selection([document.querySelectorAll(selector)], [document.documentElement]) : new Selection([selector == null ? [] : selector], root);
  }

  function touch (node, touches, identifier) {
    if (arguments.length < 3) identifier = touches, touches = sourceEvent().changedTouches;

    for (var i = 0, n = touches ? touches.length : 0, touch; i < n; ++i) {
      if ((touch = touches[i]).identifier === identifier) {
        return point(node, touch);
      }
    }

    return null;
  }

  function touches (node, touches) {
    if (touches == null) touches = sourceEvent().touches;

    for (var i = 0, n = touches ? touches.length : 0, points = new Array(n); i < n; ++i) {
      points[i] = point(node, touches[i]);
    }

    return points;
  }

  function nopropagation() {
    exports.event.stopImmediatePropagation();
  }
  function noevent () {
    exports.event.preventDefault();
    exports.event.stopImmediatePropagation();
  }

  function dragDisable (view) {
    var root = view.document.documentElement,
        selection$$1 = select(view).on("dragstart.drag", noevent, true);

    if ("onselectstart" in root) {
      selection$$1.on("selectstart.drag", noevent, true);
    } else {
      root.__noselect = root.style.MozUserSelect;
      root.style.MozUserSelect = "none";
    }
  }
  function yesdrag(view, noclick) {
    var root = view.document.documentElement,
        selection$$1 = select(view).on("dragstart.drag", null);

    if (noclick) {
      selection$$1.on("click.drag", noevent, true);
      setTimeout(function () {
        selection$$1.on("click.drag", null);
      }, 0);
    }

    if ("onselectstart" in root) {
      selection$$1.on("selectstart.drag", null);
    } else {
      root.style.MozUserSelect = root.__noselect;
      delete root.__noselect;
    }
  }

  function constant$2 (x) {
    return function () {
      return x;
    };
  }

  function DragEvent(target, type, subject, id, active, x, y, dx, dy, dispatch) {
    this.target = target;
    this.type = type;
    this.subject = subject;
    this.identifier = id;
    this.active = active;
    this.x = x;
    this.y = y;
    this.dx = dx;
    this.dy = dy;
    this._ = dispatch;
  }

  DragEvent.prototype.on = function () {
    var value = this._.on.apply(this._, arguments);

    return value === this._ ? this : value;
  };

  function defaultFilter() {
    return !exports.event.button;
  }

  function defaultContainer() {
    return this.parentNode;
  }

  function defaultSubject(d) {
    return d == null ? {
      x: exports.event.x,
      y: exports.event.y
    } : d;
  }

  function defaultTouchable() {
    return "ontouchstart" in this;
  }

  function drag () {
    var filter = defaultFilter,
        container = defaultContainer,
        subject = defaultSubject,
        touchable = defaultTouchable,
        gestures = {},
        listeners = dispatch("start", "drag", "end"),
        active = 0,
        mousedownx,
        mousedowny,
        mousemoving,
        touchending,
        clickDistance2 = 0;

    function drag(selection$$1) {
      selection$$1.on("mousedown.drag", mousedowned).filter(touchable).on("touchstart.drag", touchstarted).on("touchmove.drag", touchmoved).on("touchend.drag touchcancel.drag", touchended).style("touch-action", "none").style("-webkit-tap-highlight-color", "rgba(0,0,0,0)");
    }

    function mousedowned() {
      if (touchending || !filter.apply(this, arguments)) return;
      var gesture = beforestart("mouse", container.apply(this, arguments), mouse, this, arguments);
      if (!gesture) return;
      select(exports.event.view).on("mousemove.drag", mousemoved, true).on("mouseup.drag", mouseupped, true);
      dragDisable(exports.event.view);
      nopropagation();
      mousemoving = false;
      mousedownx = exports.event.clientX;
      mousedowny = exports.event.clientY;
      gesture("start");
    }

    function mousemoved() {
      noevent();

      if (!mousemoving) {
        var dx = exports.event.clientX - mousedownx,
            dy = exports.event.clientY - mousedowny;
        mousemoving = dx * dx + dy * dy > clickDistance2;
      }

      gestures.mouse("drag");
    }

    function mouseupped() {
      select(exports.event.view).on("mousemove.drag mouseup.drag", null);
      yesdrag(exports.event.view, mousemoving);
      noevent();
      gestures.mouse("end");
    }

    function touchstarted() {
      if (!filter.apply(this, arguments)) return;
      var touches$$1 = exports.event.changedTouches,
          c = container.apply(this, arguments),
          n = touches$$1.length,
          i,
          gesture;

      for (i = 0; i < n; ++i) {
        if (gesture = beforestart(touches$$1[i].identifier, c, touch, this, arguments)) {
          nopropagation();
          gesture("start");
        }
      }
    }

    function touchmoved() {
      var touches$$1 = exports.event.changedTouches,
          n = touches$$1.length,
          i,
          gesture;

      for (i = 0; i < n; ++i) {
        if (gesture = gestures[touches$$1[i].identifier]) {
          noevent();
          gesture("drag");
        }
      }
    }

    function touchended() {
      var touches$$1 = exports.event.changedTouches,
          n = touches$$1.length,
          i,
          gesture;
      if (touchending) clearTimeout(touchending);
      touchending = setTimeout(function () {
        touchending = null;
      }, 500); // Ghost clicks are delayed!

      for (i = 0; i < n; ++i) {
        if (gesture = gestures[touches$$1[i].identifier]) {
          nopropagation();
          gesture("end");
        }
      }
    }

    function beforestart(id, container, point$$1, that, args) {
      var p = point$$1(container, id),
          s,
          dx,
          dy,
          sublisteners = listeners.copy();
      if (!customEvent(new DragEvent(drag, "beforestart", s, id, active, p[0], p[1], 0, 0, sublisteners), function () {
        if ((exports.event.subject = s = subject.apply(that, args)) == null) return false;
        dx = s.x - p[0] || 0;
        dy = s.y - p[1] || 0;
        return true;
      })) return;
      return function gesture(type) {
        var p0 = p,
            n;

        switch (type) {
          case "start":
            gestures[id] = gesture, n = active++;
            break;

          case "end":
            delete gestures[id], --active;
          // nobreak

          case "drag":
            p = point$$1(container, id), n = active;
            break;
        }

        customEvent(new DragEvent(drag, type, s, id, n, p[0] + dx, p[1] + dy, p[0] - p0[0], p[1] - p0[1], sublisteners), sublisteners.apply, sublisteners, [type, that, args]);
      };
    }

    drag.filter = function (_) {
      return arguments.length ? (filter = typeof _ === "function" ? _ : constant$2(!!_), drag) : filter;
    };

    drag.container = function (_) {
      return arguments.length ? (container = typeof _ === "function" ? _ : constant$2(_), drag) : container;
    };

    drag.subject = function (_) {
      return arguments.length ? (subject = typeof _ === "function" ? _ : constant$2(_), drag) : subject;
    };

    drag.touchable = function (_) {
      return arguments.length ? (touchable = typeof _ === "function" ? _ : constant$2(!!_), drag) : touchable;
    };

    drag.on = function () {
      var value = listeners.on.apply(listeners, arguments);
      return value === listeners ? drag : value;
    };

    drag.clickDistance = function (_) {
      return arguments.length ? (clickDistance2 = (_ = +_) * _, drag) : Math.sqrt(clickDistance2);
    };

    return drag;
  }

  function define (constructor, factory, prototype) {
    constructor.prototype = factory.prototype = prototype;
    prototype.constructor = constructor;
  }
  function extend(parent, definition) {
    var prototype = Object.create(parent.prototype);

    for (var key in definition) {
      prototype[key] = definition[key];
    }

    return prototype;
  }

  function Color() {}
  var _darker = 0.7;

  var _brighter = 1 / _darker;
  var reI = "\\s*([+-]?\\d+)\\s*",
      reN = "\\s*([+-]?\\d*\\.?\\d+(?:[eE][+-]?\\d+)?)\\s*",
      reP = "\\s*([+-]?\\d*\\.?\\d+(?:[eE][+-]?\\d+)?)%\\s*",
      reHex3 = /^#([0-9a-f]{3})$/,
      reHex6 = /^#([0-9a-f]{6})$/,
      reRgbInteger = new RegExp("^rgb\\(" + [reI, reI, reI] + "\\)$"),
      reRgbPercent = new RegExp("^rgb\\(" + [reP, reP, reP] + "\\)$"),
      reRgbaInteger = new RegExp("^rgba\\(" + [reI, reI, reI, reN] + "\\)$"),
      reRgbaPercent = new RegExp("^rgba\\(" + [reP, reP, reP, reN] + "\\)$"),
      reHslPercent = new RegExp("^hsl\\(" + [reN, reP, reP] + "\\)$"),
      reHslaPercent = new RegExp("^hsla\\(" + [reN, reP, reP, reN] + "\\)$");
  var named = {
    aliceblue: 0xf0f8ff,
    antiquewhite: 0xfaebd7,
    aqua: 0x00ffff,
    aquamarine: 0x7fffd4,
    azure: 0xf0ffff,
    beige: 0xf5f5dc,
    bisque: 0xffe4c4,
    black: 0x000000,
    blanchedalmond: 0xffebcd,
    blue: 0x0000ff,
    blueviolet: 0x8a2be2,
    brown: 0xa52a2a,
    burlywood: 0xdeb887,
    cadetblue: 0x5f9ea0,
    chartreuse: 0x7fff00,
    chocolate: 0xd2691e,
    coral: 0xff7f50,
    cornflowerblue: 0x6495ed,
    cornsilk: 0xfff8dc,
    crimson: 0xdc143c,
    cyan: 0x00ffff,
    darkblue: 0x00008b,
    darkcyan: 0x008b8b,
    darkgoldenrod: 0xb8860b,
    darkgray: 0xa9a9a9,
    darkgreen: 0x006400,
    darkgrey: 0xa9a9a9,
    darkkhaki: 0xbdb76b,
    darkmagenta: 0x8b008b,
    darkolivegreen: 0x556b2f,
    darkorange: 0xff8c00,
    darkorchid: 0x9932cc,
    darkred: 0x8b0000,
    darksalmon: 0xe9967a,
    darkseagreen: 0x8fbc8f,
    darkslateblue: 0x483d8b,
    darkslategray: 0x2f4f4f,
    darkslategrey: 0x2f4f4f,
    darkturquoise: 0x00ced1,
    darkviolet: 0x9400d3,
    deeppink: 0xff1493,
    deepskyblue: 0x00bfff,
    dimgray: 0x696969,
    dimgrey: 0x696969,
    dodgerblue: 0x1e90ff,
    firebrick: 0xb22222,
    floralwhite: 0xfffaf0,
    forestgreen: 0x228b22,
    fuchsia: 0xff00ff,
    gainsboro: 0xdcdcdc,
    ghostwhite: 0xf8f8ff,
    gold: 0xffd700,
    goldenrod: 0xdaa520,
    gray: 0x808080,
    green: 0x008000,
    greenyellow: 0xadff2f,
    grey: 0x808080,
    honeydew: 0xf0fff0,
    hotpink: 0xff69b4,
    indianred: 0xcd5c5c,
    indigo: 0x4b0082,
    ivory: 0xfffff0,
    khaki: 0xf0e68c,
    lavender: 0xe6e6fa,
    lavenderblush: 0xfff0f5,
    lawngreen: 0x7cfc00,
    lemonchiffon: 0xfffacd,
    lightblue: 0xadd8e6,
    lightcoral: 0xf08080,
    lightcyan: 0xe0ffff,
    lightgoldenrodyellow: 0xfafad2,
    lightgray: 0xd3d3d3,
    lightgreen: 0x90ee90,
    lightgrey: 0xd3d3d3,
    lightpink: 0xffb6c1,
    lightsalmon: 0xffa07a,
    lightseagreen: 0x20b2aa,
    lightskyblue: 0x87cefa,
    lightslategray: 0x778899,
    lightslategrey: 0x778899,
    lightsteelblue: 0xb0c4de,
    lightyellow: 0xffffe0,
    lime: 0x00ff00,
    limegreen: 0x32cd32,
    linen: 0xfaf0e6,
    magenta: 0xff00ff,
    maroon: 0x800000,
    mediumaquamarine: 0x66cdaa,
    mediumblue: 0x0000cd,
    mediumorchid: 0xba55d3,
    mediumpurple: 0x9370db,
    mediumseagreen: 0x3cb371,
    mediumslateblue: 0x7b68ee,
    mediumspringgreen: 0x00fa9a,
    mediumturquoise: 0x48d1cc,
    mediumvioletred: 0xc71585,
    midnightblue: 0x191970,
    mintcream: 0xf5fffa,
    mistyrose: 0xffe4e1,
    moccasin: 0xffe4b5,
    navajowhite: 0xffdead,
    navy: 0x000080,
    oldlace: 0xfdf5e6,
    olive: 0x808000,
    olivedrab: 0x6b8e23,
    orange: 0xffa500,
    orangered: 0xff4500,
    orchid: 0xda70d6,
    palegoldenrod: 0xeee8aa,
    palegreen: 0x98fb98,
    paleturquoise: 0xafeeee,
    palevioletred: 0xdb7093,
    papayawhip: 0xffefd5,
    peachpuff: 0xffdab9,
    peru: 0xcd853f,
    pink: 0xffc0cb,
    plum: 0xdda0dd,
    powderblue: 0xb0e0e6,
    purple: 0x800080,
    rebeccapurple: 0x663399,
    red: 0xff0000,
    rosybrown: 0xbc8f8f,
    royalblue: 0x4169e1,
    saddlebrown: 0x8b4513,
    salmon: 0xfa8072,
    sandybrown: 0xf4a460,
    seagreen: 0x2e8b57,
    seashell: 0xfff5ee,
    sienna: 0xa0522d,
    silver: 0xc0c0c0,
    skyblue: 0x87ceeb,
    slateblue: 0x6a5acd,
    slategray: 0x708090,
    slategrey: 0x708090,
    snow: 0xfffafa,
    springgreen: 0x00ff7f,
    steelblue: 0x4682b4,
    tan: 0xd2b48c,
    teal: 0x008080,
    thistle: 0xd8bfd8,
    tomato: 0xff6347,
    turquoise: 0x40e0d0,
    violet: 0xee82ee,
    wheat: 0xf5deb3,
    white: 0xffffff,
    whitesmoke: 0xf5f5f5,
    yellow: 0xffff00,
    yellowgreen: 0x9acd32
  };
  define(Color, color, {
    displayable: function displayable() {
      return this.rgb().displayable();
    },
    hex: function hex() {
      return this.rgb().hex();
    },
    toString: function toString() {
      return this.rgb() + "";
    }
  });
  function color(format) {
    var m;
    format = (format + "").trim().toLowerCase();
    return (m = reHex3.exec(format)) ? (m = parseInt(m[1], 16), new Rgb(m >> 8 & 0xf | m >> 4 & 0x0f0, m >> 4 & 0xf | m & 0xf0, (m & 0xf) << 4 | m & 0xf, 1) // #f00
    ) : (m = reHex6.exec(format)) ? rgbn(parseInt(m[1], 16)) // #ff0000
    : (m = reRgbInteger.exec(format)) ? new Rgb(m[1], m[2], m[3], 1) // rgb(255, 0, 0)
    : (m = reRgbPercent.exec(format)) ? new Rgb(m[1] * 255 / 100, m[2] * 255 / 100, m[3] * 255 / 100, 1) // rgb(100%, 0%, 0%)
    : (m = reRgbaInteger.exec(format)) ? rgba(m[1], m[2], m[3], m[4]) // rgba(255, 0, 0, 1)
    : (m = reRgbaPercent.exec(format)) ? rgba(m[1] * 255 / 100, m[2] * 255 / 100, m[3] * 255 / 100, m[4]) // rgb(100%, 0%, 0%, 1)
    : (m = reHslPercent.exec(format)) ? hsla(m[1], m[2] / 100, m[3] / 100, 1) // hsl(120, 50%, 50%)
    : (m = reHslaPercent.exec(format)) ? hsla(m[1], m[2] / 100, m[3] / 100, m[4]) // hsla(120, 50%, 50%, 1)
    : named.hasOwnProperty(format) ? rgbn(named[format]) : format === "transparent" ? new Rgb(NaN, NaN, NaN, 0) : null;
  }

  function rgbn(n) {
    return new Rgb(n >> 16 & 0xff, n >> 8 & 0xff, n & 0xff, 1);
  }

  function rgba(r, g, b, a) {
    if (a <= 0) r = g = b = NaN;
    return new Rgb(r, g, b, a);
  }

  function rgbConvert(o) {
    if (!(o instanceof Color)) o = color(o);
    if (!o) return new Rgb();
    o = o.rgb();
    return new Rgb(o.r, o.g, o.b, o.opacity);
  }
  function rgb(r, g, b, opacity) {
    return arguments.length === 1 ? rgbConvert(r) : new Rgb(r, g, b, opacity == null ? 1 : opacity);
  }
  function Rgb(r, g, b, opacity) {
    this.r = +r;
    this.g = +g;
    this.b = +b;
    this.opacity = +opacity;
  }
  define(Rgb, rgb, extend(Color, {
    brighter: function brighter(k) {
      k = k == null ? _brighter : Math.pow(_brighter, k);
      return new Rgb(this.r * k, this.g * k, this.b * k, this.opacity);
    },
    darker: function darker(k) {
      k = k == null ? _darker : Math.pow(_darker, k);
      return new Rgb(this.r * k, this.g * k, this.b * k, this.opacity);
    },
    rgb: function rgb() {
      return this;
    },
    displayable: function displayable() {
      return 0 <= this.r && this.r <= 255 && 0 <= this.g && this.g <= 255 && 0 <= this.b && this.b <= 255 && 0 <= this.opacity && this.opacity <= 1;
    },
    hex: function hex() {
      return "#" + _hex(this.r) + _hex(this.g) + _hex(this.b);
    },
    toString: function toString() {
      var a = this.opacity;
      a = isNaN(a) ? 1 : Math.max(0, Math.min(1, a));
      return (a === 1 ? "rgb(" : "rgba(") + Math.max(0, Math.min(255, Math.round(this.r) || 0)) + ", " + Math.max(0, Math.min(255, Math.round(this.g) || 0)) + ", " + Math.max(0, Math.min(255, Math.round(this.b) || 0)) + (a === 1 ? ")" : ", " + a + ")");
    }
  }));

  function _hex(value) {
    value = Math.max(0, Math.min(255, Math.round(value) || 0));
    return (value < 16 ? "0" : "") + value.toString(16);
  }

  function hsla(h, s, l, a) {
    if (a <= 0) h = s = l = NaN;else if (l <= 0 || l >= 1) h = s = NaN;else if (s <= 0) h = NaN;
    return new Hsl(h, s, l, a);
  }

  function hslConvert(o) {
    if (o instanceof Hsl) return new Hsl(o.h, o.s, o.l, o.opacity);
    if (!(o instanceof Color)) o = color(o);
    if (!o) return new Hsl();
    if (o instanceof Hsl) return o;
    o = o.rgb();
    var r = o.r / 255,
        g = o.g / 255,
        b = o.b / 255,
        min = Math.min(r, g, b),
        max = Math.max(r, g, b),
        h = NaN,
        s = max - min,
        l = (max + min) / 2;

    if (s) {
      if (r === max) h = (g - b) / s + (g < b) * 6;else if (g === max) h = (b - r) / s + 2;else h = (r - g) / s + 4;
      s /= l < 0.5 ? max + min : 2 - max - min;
      h *= 60;
    } else {
      s = l > 0 && l < 1 ? 0 : h;
    }

    return new Hsl(h, s, l, o.opacity);
  }
  function hsl(h, s, l, opacity) {
    return arguments.length === 1 ? hslConvert(h) : new Hsl(h, s, l, opacity == null ? 1 : opacity);
  }

  function Hsl(h, s, l, opacity) {
    this.h = +h;
    this.s = +s;
    this.l = +l;
    this.opacity = +opacity;
  }

  define(Hsl, hsl, extend(Color, {
    brighter: function brighter(k) {
      k = k == null ? _brighter : Math.pow(_brighter, k);
      return new Hsl(this.h, this.s, this.l * k, this.opacity);
    },
    darker: function darker(k) {
      k = k == null ? _darker : Math.pow(_darker, k);
      return new Hsl(this.h, this.s, this.l * k, this.opacity);
    },
    rgb: function rgb() {
      var h = this.h % 360 + (this.h < 0) * 360,
          s = isNaN(h) || isNaN(this.s) ? 0 : this.s,
          l = this.l,
          m2 = l + (l < 0.5 ? l : 1 - l) * s,
          m1 = 2 * l - m2;
      return new Rgb(hsl2rgb(h >= 240 ? h - 240 : h + 120, m1, m2), hsl2rgb(h, m1, m2), hsl2rgb(h < 120 ? h + 240 : h - 120, m1, m2), this.opacity);
    },
    displayable: function displayable() {
      return (0 <= this.s && this.s <= 1 || isNaN(this.s)) && 0 <= this.l && this.l <= 1 && 0 <= this.opacity && this.opacity <= 1;
    }
  }));
  /* From FvD 13.37, CSS Color Module Level 3 */

  function hsl2rgb(h, m1, m2) {
    return (h < 60 ? m1 + (m2 - m1) * h / 60 : h < 180 ? m2 : h < 240 ? m1 + (m2 - m1) * (240 - h) / 60 : m1) * 255;
  }

  var deg2rad = Math.PI / 180;
  var rad2deg = 180 / Math.PI;

  var K = 18,
      Xn = 0.96422,
      Yn = 1,
      Zn = 0.82521,
      t0 = 4 / 29,
      t1 = 6 / 29,
      t2 = 3 * t1 * t1,
      t3 = t1 * t1 * t1;

  function labConvert(o) {
    if (o instanceof Lab) return new Lab(o.l, o.a, o.b, o.opacity);

    if (o instanceof Hcl) {
      if (isNaN(o.h)) return new Lab(o.l, 0, 0, o.opacity);
      var h = o.h * deg2rad;
      return new Lab(o.l, Math.cos(h) * o.c, Math.sin(h) * o.c, o.opacity);
    }

    if (!(o instanceof Rgb)) o = rgbConvert(o);
    var r = rgb2lrgb(o.r),
        g = rgb2lrgb(o.g),
        b = rgb2lrgb(o.b),
        y = xyz2lab((0.2225045 * r + 0.7168786 * g + 0.0606169 * b) / Yn),
        x,
        z;
    if (r === g && g === b) x = z = y;else {
      x = xyz2lab((0.4360747 * r + 0.3850649 * g + 0.1430804 * b) / Xn);
      z = xyz2lab((0.0139322 * r + 0.0971045 * g + 0.7141733 * b) / Zn);
    }
    return new Lab(116 * y - 16, 500 * (x - y), 200 * (y - z), o.opacity);
  }

  function gray(l, opacity) {
    return new Lab(l, 0, 0, opacity == null ? 1 : opacity);
  }
  function lab(l, a, b, opacity) {
    return arguments.length === 1 ? labConvert(l) : new Lab(l, a, b, opacity == null ? 1 : opacity);
  }
  function Lab(l, a, b, opacity) {
    this.l = +l;
    this.a = +a;
    this.b = +b;
    this.opacity = +opacity;
  }
  define(Lab, lab, extend(Color, {
    brighter: function brighter(k) {
      return new Lab(this.l + K * (k == null ? 1 : k), this.a, this.b, this.opacity);
    },
    darker: function darker(k) {
      return new Lab(this.l - K * (k == null ? 1 : k), this.a, this.b, this.opacity);
    },
    rgb: function rgb$$1() {
      var y = (this.l + 16) / 116,
          x = isNaN(this.a) ? y : y + this.a / 500,
          z = isNaN(this.b) ? y : y - this.b / 200;
      x = Xn * lab2xyz(x);
      y = Yn * lab2xyz(y);
      z = Zn * lab2xyz(z);
      return new Rgb(lrgb2rgb(3.1338561 * x - 1.6168667 * y - 0.4906146 * z), lrgb2rgb(-0.9787684 * x + 1.9161415 * y + 0.0334540 * z), lrgb2rgb(0.0719453 * x - 0.2289914 * y + 1.4052427 * z), this.opacity);
    }
  }));

  function xyz2lab(t) {
    return t > t3 ? Math.pow(t, 1 / 3) : t / t2 + t0;
  }

  function lab2xyz(t) {
    return t > t1 ? t * t * t : t2 * (t - t0);
  }

  function lrgb2rgb(x) {
    return 255 * (x <= 0.0031308 ? 12.92 * x : 1.055 * Math.pow(x, 1 / 2.4) - 0.055);
  }

  function rgb2lrgb(x) {
    return (x /= 255) <= 0.04045 ? x / 12.92 : Math.pow((x + 0.055) / 1.055, 2.4);
  }

  function hclConvert(o) {
    if (o instanceof Hcl) return new Hcl(o.h, o.c, o.l, o.opacity);
    if (!(o instanceof Lab)) o = labConvert(o);
    if (o.a === 0 && o.b === 0) return new Hcl(NaN, 0, o.l, o.opacity);
    var h = Math.atan2(o.b, o.a) * rad2deg;
    return new Hcl(h < 0 ? h + 360 : h, Math.sqrt(o.a * o.a + o.b * o.b), o.l, o.opacity);
  }

  function lch(l, c, h, opacity) {
    return arguments.length === 1 ? hclConvert(l) : new Hcl(h, c, l, opacity == null ? 1 : opacity);
  }
  function hcl(h, c, l, opacity) {
    return arguments.length === 1 ? hclConvert(h) : new Hcl(h, c, l, opacity == null ? 1 : opacity);
  }
  function Hcl(h, c, l, opacity) {
    this.h = +h;
    this.c = +c;
    this.l = +l;
    this.opacity = +opacity;
  }
  define(Hcl, hcl, extend(Color, {
    brighter: function brighter(k) {
      return new Hcl(this.h, this.c, this.l + K * (k == null ? 1 : k), this.opacity);
    },
    darker: function darker(k) {
      return new Hcl(this.h, this.c, this.l - K * (k == null ? 1 : k), this.opacity);
    },
    rgb: function rgb$$1() {
      return labConvert(this).rgb();
    }
  }));

  var A = -0.14861,
      B = +1.78277,
      C = -0.29227,
      D = -0.90649,
      E = +1.97294,
      ED = E * D,
      EB = E * B,
      BC_DA = B * C - D * A;

  function cubehelixConvert(o) {
    if (o instanceof Cubehelix) return new Cubehelix(o.h, o.s, o.l, o.opacity);
    if (!(o instanceof Rgb)) o = rgbConvert(o);
    var r = o.r / 255,
        g = o.g / 255,
        b = o.b / 255,
        l = (BC_DA * b + ED * r - EB * g) / (BC_DA + ED - EB),
        bl = b - l,
        k = (E * (g - l) - C * bl) / D,
        s = Math.sqrt(k * k + bl * bl) / (E * l * (1 - l)),
        // NaN if l=0 or l=1
    h = s ? Math.atan2(k, bl) * rad2deg - 120 : NaN;
    return new Cubehelix(h < 0 ? h + 360 : h, s, l, o.opacity);
  }

  function cubehelix(h, s, l, opacity) {
    return arguments.length === 1 ? cubehelixConvert(h) : new Cubehelix(h, s, l, opacity == null ? 1 : opacity);
  }
  function Cubehelix(h, s, l, opacity) {
    this.h = +h;
    this.s = +s;
    this.l = +l;
    this.opacity = +opacity;
  }
  define(Cubehelix, cubehelix, extend(Color, {
    brighter: function brighter$$1(k) {
      k = k == null ? _brighter : Math.pow(_brighter, k);
      return new Cubehelix(this.h, this.s, this.l * k, this.opacity);
    },
    darker: function darker$$1(k) {
      k = k == null ? _darker : Math.pow(_darker, k);
      return new Cubehelix(this.h, this.s, this.l * k, this.opacity);
    },
    rgb: function rgb$$1() {
      var h = isNaN(this.h) ? 0 : (this.h + 120) * deg2rad,
          l = +this.l,
          a = isNaN(this.s) ? 0 : this.s * l * (1 - l),
          cosh = Math.cos(h),
          sinh = Math.sin(h);
      return new Rgb(255 * (l + a * (A * cosh + B * sinh)), 255 * (l + a * (C * cosh + D * sinh)), 255 * (l + a * (E * cosh)), this.opacity);
    }
  }));

  function basis(t1, v0, v1, v2, v3) {
    var t2 = t1 * t1,
        t3 = t2 * t1;
    return ((1 - 3 * t1 + 3 * t2 - t3) * v0 + (4 - 6 * t2 + 3 * t3) * v1 + (1 + 3 * t1 + 3 * t2 - 3 * t3) * v2 + t3 * v3) / 6;
  }
  function basis$1 (values) {
    var n = values.length - 1;
    return function (t) {
      var i = t <= 0 ? t = 0 : t >= 1 ? (t = 1, n - 1) : Math.floor(t * n),
          v1 = values[i],
          v2 = values[i + 1],
          v0 = i > 0 ? values[i - 1] : 2 * v1 - v2,
          v3 = i < n - 1 ? values[i + 2] : 2 * v2 - v1;
      return basis((t - i / n) * n, v0, v1, v2, v3);
    };
  }

  function basisClosed (values) {
    var n = values.length;
    return function (t) {
      var i = Math.floor(((t %= 1) < 0 ? ++t : t) * n),
          v0 = values[(i + n - 1) % n],
          v1 = values[i % n],
          v2 = values[(i + 1) % n],
          v3 = values[(i + 2) % n];
      return basis((t - i / n) * n, v0, v1, v2, v3);
    };
  }

  function constant$3 (x) {
    return function () {
      return x;
    };
  }

  function linear(a, d) {
    return function (t) {
      return a + t * d;
    };
  }

  function exponential(a, b, y) {
    return a = Math.pow(a, y), b = Math.pow(b, y) - a, y = 1 / y, function (t) {
      return Math.pow(a + t * b, y);
    };
  }

  function hue(a, b) {
    var d = b - a;
    return d ? linear(a, d > 180 || d < -180 ? d - 360 * Math.round(d / 360) : d) : constant$3(isNaN(a) ? b : a);
  }
  function gamma(y) {
    return (y = +y) === 1 ? nogamma : function (a, b) {
      return b - a ? exponential(a, b, y) : constant$3(isNaN(a) ? b : a);
    };
  }
  function nogamma(a, b) {
    var d = b - a;
    return d ? linear(a, d) : constant$3(isNaN(a) ? b : a);
  }

  var interpolateRgb = (function rgbGamma(y) {
    var color$$1 = gamma(y);

    function rgb$$1(start, end) {
      var r = color$$1((start = rgb(start)).r, (end = rgb(end)).r),
          g = color$$1(start.g, end.g),
          b = color$$1(start.b, end.b),
          opacity = nogamma(start.opacity, end.opacity);
      return function (t) {
        start.r = r(t);
        start.g = g(t);
        start.b = b(t);
        start.opacity = opacity(t);
        return start + "";
      };
    }

    rgb$$1.gamma = rgbGamma;
    return rgb$$1;
  })(1);

  function rgbSpline(spline) {
    return function (colors) {
      var n = colors.length,
          r = new Array(n),
          g = new Array(n),
          b = new Array(n),
          i,
          color$$1;

      for (i = 0; i < n; ++i) {
        color$$1 = rgb(colors[i]);
        r[i] = color$$1.r || 0;
        g[i] = color$$1.g || 0;
        b[i] = color$$1.b || 0;
      }

      r = spline(r);
      g = spline(g);
      b = spline(b);
      color$$1.opacity = 1;
      return function (t) {
        color$$1.r = r(t);
        color$$1.g = g(t);
        color$$1.b = b(t);
        return color$$1 + "";
      };
    };
  }

  var rgbBasis = rgbSpline(basis$1);
  var rgbBasisClosed = rgbSpline(basisClosed);

  function array$1 (a, b) {
    var nb = b ? b.length : 0,
        na = a ? Math.min(nb, a.length) : 0,
        x = new Array(na),
        c = new Array(nb),
        i;

    for (i = 0; i < na; ++i) {
      x[i] = interpolateValue(a[i], b[i]);
    }

    for (; i < nb; ++i) {
      c[i] = b[i];
    }

    return function (t) {
      for (i = 0; i < na; ++i) {
        c[i] = x[i](t);
      }

      return c;
    };
  }

  function date (a, b) {
    var d = new Date();
    return a = +a, b -= a, function (t) {
      return d.setTime(a + b * t), d;
    };
  }

  function interpolateNumber (a, b) {
    return a = +a, b -= a, function (t) {
      return a + b * t;
    };
  }

  function object (a, b) {
    var i = {},
        c = {},
        k;
    if (a === null || babelHelpers.typeof(a) !== "object") a = {};
    if (b === null || babelHelpers.typeof(b) !== "object") b = {};

    for (k in b) {
      if (k in a) {
        i[k] = interpolateValue(a[k], b[k]);
      } else {
        c[k] = b[k];
      }
    }

    return function (t) {
      for (k in i) {
        c[k] = i[k](t);
      }

      return c;
    };
  }

  var reA = /[-+]?(?:\d+\.?\d*|\.?\d+)(?:[eE][-+]?\d+)?/g,
      reB = new RegExp(reA.source, "g");

  function zero(b) {
    return function () {
      return b;
    };
  }

  function one(b) {
    return function (t) {
      return b(t) + "";
    };
  }

  function interpolateString (a, b) {
    var bi = reA.lastIndex = reB.lastIndex = 0,
        // scan index for next number in b
    am,
        // current match in a
    bm,
        // current match in b
    bs,
        // string preceding current number in b, if any
    i = -1,
        // index in s
    s = [],
        // string constants and placeholders
    q = []; // number interpolators
    // Coerce inputs to strings.

    a = a + "", b = b + ""; // Interpolate pairs of numbers in a & b.

    while ((am = reA.exec(a)) && (bm = reB.exec(b))) {
      if ((bs = bm.index) > bi) {
        // a string precedes the next number in b
        bs = b.slice(bi, bs);
        if (s[i]) s[i] += bs; // coalesce with previous string
        else s[++i] = bs;
      }

      if ((am = am[0]) === (bm = bm[0])) {
        // numbers in a & b match
        if (s[i]) s[i] += bm; // coalesce with previous string
        else s[++i] = bm;
      } else {
        // interpolate non-matching numbers
        s[++i] = null;
        q.push({
          i: i,
          x: interpolateNumber(am, bm)
        });
      }

      bi = reB.lastIndex;
    } // Add remains of b.


    if (bi < b.length) {
      bs = b.slice(bi);
      if (s[i]) s[i] += bs; // coalesce with previous string
      else s[++i] = bs;
    } // Special optimization for only a single match.
    // Otherwise, interpolate each of the numbers and rejoin the string.


    return s.length < 2 ? q[0] ? one(q[0].x) : zero(b) : (b = q.length, function (t) {
      for (var i = 0, o; i < b; ++i) {
        s[(o = q[i]).i] = o.x(t);
      }

      return s.join("");
    });
  }

  function interpolateValue (a, b) {
    var t = babelHelpers.typeof(b),
        c;
    return b == null || t === "boolean" ? constant$3(b) : (t === "number" ? interpolateNumber : t === "string" ? (c = color(b)) ? (b = c, interpolateRgb) : interpolateString : b instanceof color ? interpolateRgb : b instanceof Date ? date : Array.isArray(b) ? array$1 : typeof b.valueOf !== "function" && typeof b.toString !== "function" || isNaN(b) ? object : interpolateNumber)(a, b);
  }

  function discrete (range) {
    var n = range.length;
    return function (t) {
      return range[Math.max(0, Math.min(n - 1, Math.floor(t * n)))];
    };
  }

  function hue$1 (a, b) {
    var i = hue(+a, +b);
    return function (t) {
      var x = i(t);
      return x - 360 * Math.floor(x / 360);
    };
  }

  function interpolateRound (a, b) {
    return a = +a, b -= a, function (t) {
      return Math.round(a + b * t);
    };
  }

  var degrees = 180 / Math.PI;
  var identity$2 = {
    translateX: 0,
    translateY: 0,
    rotate: 0,
    skewX: 0,
    scaleX: 1,
    scaleY: 1
  };
  function decompose (a, b, c, d, e, f) {
    var scaleX, scaleY, skewX;
    if (scaleX = Math.sqrt(a * a + b * b)) a /= scaleX, b /= scaleX;
    if (skewX = a * c + b * d) c -= a * skewX, d -= b * skewX;
    if (scaleY = Math.sqrt(c * c + d * d)) c /= scaleY, d /= scaleY, skewX /= scaleY;
    if (a * d < b * c) a = -a, b = -b, skewX = -skewX, scaleX = -scaleX;
    return {
      translateX: e,
      translateY: f,
      rotate: Math.atan2(b, a) * degrees,
      skewX: Math.atan(skewX) * degrees,
      scaleX: scaleX,
      scaleY: scaleY
    };
  }

  var cssNode, cssRoot, cssView, svgNode;
  function parseCss(value) {
    if (value === "none") return identity$2;
    if (!cssNode) cssNode = document.createElement("DIV"), cssRoot = document.documentElement, cssView = document.defaultView;
    cssNode.style.transform = value;
    value = cssView.getComputedStyle(cssRoot.appendChild(cssNode), null).getPropertyValue("transform");
    cssRoot.removeChild(cssNode);
    value = value.slice(7, -1).split(",");
    return decompose(+value[0], +value[1], +value[2], +value[3], +value[4], +value[5]);
  }
  function parseSvg(value) {
    if (value == null) return identity$2;
    if (!svgNode) svgNode = document.createElementNS("http://www.w3.org/2000/svg", "g");
    svgNode.setAttribute("transform", value);
    if (!(value = svgNode.transform.baseVal.consolidate())) return identity$2;
    value = value.matrix;
    return decompose(value.a, value.b, value.c, value.d, value.e, value.f);
  }

  function interpolateTransform(parse, pxComma, pxParen, degParen) {
    function pop(s) {
      return s.length ? s.pop() + " " : "";
    }

    function translate(xa, ya, xb, yb, s, q) {
      if (xa !== xb || ya !== yb) {
        var i = s.push("translate(", null, pxComma, null, pxParen);
        q.push({
          i: i - 4,
          x: interpolateNumber(xa, xb)
        }, {
          i: i - 2,
          x: interpolateNumber(ya, yb)
        });
      } else if (xb || yb) {
        s.push("translate(" + xb + pxComma + yb + pxParen);
      }
    }

    function rotate(a, b, s, q) {
      if (a !== b) {
        if (a - b > 180) b += 360;else if (b - a > 180) a += 360; // shortest path

        q.push({
          i: s.push(pop(s) + "rotate(", null, degParen) - 2,
          x: interpolateNumber(a, b)
        });
      } else if (b) {
        s.push(pop(s) + "rotate(" + b + degParen);
      }
    }

    function skewX(a, b, s, q) {
      if (a !== b) {
        q.push({
          i: s.push(pop(s) + "skewX(", null, degParen) - 2,
          x: interpolateNumber(a, b)
        });
      } else if (b) {
        s.push(pop(s) + "skewX(" + b + degParen);
      }
    }

    function scale(xa, ya, xb, yb, s, q) {
      if (xa !== xb || ya !== yb) {
        var i = s.push(pop(s) + "scale(", null, ",", null, ")");
        q.push({
          i: i - 4,
          x: interpolateNumber(xa, xb)
        }, {
          i: i - 2,
          x: interpolateNumber(ya, yb)
        });
      } else if (xb !== 1 || yb !== 1) {
        s.push(pop(s) + "scale(" + xb + "," + yb + ")");
      }
    }

    return function (a, b) {
      var s = [],
          // string constants and placeholders
      q = []; // number interpolators

      a = parse(a), b = parse(b);
      translate(a.translateX, a.translateY, b.translateX, b.translateY, s, q);
      rotate(a.rotate, b.rotate, s, q);
      skewX(a.skewX, b.skewX, s, q);
      scale(a.scaleX, a.scaleY, b.scaleX, b.scaleY, s, q);
      a = b = null; // gc

      return function (t) {
        var i = -1,
            n = q.length,
            o;

        while (++i < n) {
          s[(o = q[i]).i] = o.x(t);
        }

        return s.join("");
      };
    };
  }

  var interpolateTransformCss = interpolateTransform(parseCss, "px, ", "px)", "deg)");
  var interpolateTransformSvg = interpolateTransform(parseSvg, ", ", ")", ")");

  var rho = Math.SQRT2,
      rho2 = 2,
      rho4 = 4,
      epsilon2 = 1e-12;

  function cosh(x) {
    return ((x = Math.exp(x)) + 1 / x) / 2;
  }

  function sinh(x) {
    return ((x = Math.exp(x)) - 1 / x) / 2;
  }

  function tanh(x) {
    return ((x = Math.exp(2 * x)) - 1) / (x + 1);
  } // p0 = [ux0, uy0, w0]
  // p1 = [ux1, uy1, w1]


  function interpolateZoom (p0, p1) {
    var ux0 = p0[0],
        uy0 = p0[1],
        w0 = p0[2],
        ux1 = p1[0],
        uy1 = p1[1],
        w1 = p1[2],
        dx = ux1 - ux0,
        dy = uy1 - uy0,
        d2 = dx * dx + dy * dy,
        i,
        S; // Special case for u0 в‰… u1.

    if (d2 < epsilon2) {
      S = Math.log(w1 / w0) / rho;

      i = function i(t) {
        return [ux0 + t * dx, uy0 + t * dy, w0 * Math.exp(rho * t * S)];
      };
    } // General case.
    else {
        var d1 = Math.sqrt(d2),
            b0 = (w1 * w1 - w0 * w0 + rho4 * d2) / (2 * w0 * rho2 * d1),
            b1 = (w1 * w1 - w0 * w0 - rho4 * d2) / (2 * w1 * rho2 * d1),
            r0 = Math.log(Math.sqrt(b0 * b0 + 1) - b0),
            r1 = Math.log(Math.sqrt(b1 * b1 + 1) - b1);
        S = (r1 - r0) / rho;

        i = function i(t) {
          var s = t * S,
              coshr0 = cosh(r0),
              u = w0 / (rho2 * d1) * (coshr0 * tanh(rho * s + r0) - sinh(r0));
          return [ux0 + u * dx, uy0 + u * dy, w0 * coshr0 / cosh(rho * s + r0)];
        };
      }

    i.duration = S * 1000;
    return i;
  }

  function hsl$1(hue$$1) {
    return function (start, end) {
      var h = hue$$1((start = hsl(start)).h, (end = hsl(end)).h),
          s = nogamma(start.s, end.s),
          l = nogamma(start.l, end.l),
          opacity = nogamma(start.opacity, end.opacity);
      return function (t) {
        start.h = h(t);
        start.s = s(t);
        start.l = l(t);
        start.opacity = opacity(t);
        return start + "";
      };
    };
  }

  var hsl$2 = hsl$1(hue);
  var hslLong = hsl$1(nogamma);

  function lab$1(start, end) {
    var l = nogamma((start = lab(start)).l, (end = lab(end)).l),
        a = nogamma(start.a, end.a),
        b = nogamma(start.b, end.b),
        opacity = nogamma(start.opacity, end.opacity);
    return function (t) {
      start.l = l(t);
      start.a = a(t);
      start.b = b(t);
      start.opacity = opacity(t);
      return start + "";
    };
  }

  function hcl$1(hue$$1) {
    return function (start, end) {
      var h = hue$$1((start = hcl(start)).h, (end = hcl(end)).h),
          c = nogamma(start.c, end.c),
          l = nogamma(start.l, end.l),
          opacity = nogamma(start.opacity, end.opacity);
      return function (t) {
        start.h = h(t);
        start.c = c(t);
        start.l = l(t);
        start.opacity = opacity(t);
        return start + "";
      };
    };
  }

  var hcl$2 = hcl$1(hue);
  var hclLong = hcl$1(nogamma);

  function cubehelix$1(hue$$1) {
    return function cubehelixGamma(y) {
      y = +y;

      function cubehelix$$1(start, end) {
        var h = hue$$1((start = cubehelix(start)).h, (end = cubehelix(end)).h),
            s = nogamma(start.s, end.s),
            l = nogamma(start.l, end.l),
            opacity = nogamma(start.opacity, end.opacity);
        return function (t) {
          start.h = h(t);
          start.s = s(t);
          start.l = l(Math.pow(t, y));
          start.opacity = opacity(t);
          return start + "";
        };
      }

      cubehelix$$1.gamma = cubehelixGamma;
      return cubehelix$$1;
    }(1);
  }

  var cubehelix$2 = cubehelix$1(hue);
  var cubehelixLong = cubehelix$1(nogamma);

  function piecewise(interpolate, values) {
    var i = 0,
        n = values.length - 1,
        v = values[0],
        I = new Array(n < 0 ? 0 : n);

    while (i < n) {
      I[i] = interpolate(v, v = values[++i]);
    }

    return function (t) {
      var i = Math.max(0, Math.min(n - 1, Math.floor(t *= n)));
      return I[i](t - i);
    };
  }

  function quantize (interpolator, n) {
    var samples = new Array(n);

    for (var i = 0; i < n; ++i) {
      samples[i] = interpolator(i / (n - 1));
    }

    return samples;
  }

  var frame = 0,
      // is an animation frame pending?
  timeout = 0,
      // is a timeout pending?
  interval = 0,
      // are any timers active?
  pokeDelay = 1000,
      // how frequently we check for clock skew
  taskHead,
      taskTail,
      clockLast = 0,
      clockNow = 0,
      clockSkew = 0,
      clock = (typeof performance === "undefined" ? "undefined" : babelHelpers.typeof(performance)) === "object" && performance.now ? performance : Date,
      setFrame = (typeof window === "undefined" ? "undefined" : babelHelpers.typeof(window)) === "object" && window.requestAnimationFrame ? window.requestAnimationFrame.bind(window) : function (f) {
    setTimeout(f, 17);
  };
  function now() {
    return clockNow || (setFrame(clearNow), clockNow = clock.now() + clockSkew);
  }

  function clearNow() {
    clockNow = 0;
  }

  function Timer() {
    this._call = this._time = this._next = null;
  }
  Timer.prototype = timer.prototype = {
    constructor: Timer,
    restart: function restart(callback, delay, time) {
      if (typeof callback !== "function") throw new TypeError("callback is not a function");
      time = (time == null ? now() : +time) + (delay == null ? 0 : +delay);

      if (!this._next && taskTail !== this) {
        if (taskTail) taskTail._next = this;else taskHead = this;
        taskTail = this;
      }

      this._call = callback;
      this._time = time;
      sleep();
    },
    stop: function stop() {
      if (this._call) {
        this._call = null;
        this._time = Infinity;
        sleep();
      }
    }
  };
  function timer(callback, delay, time) {
    var t = new Timer();
    t.restart(callback, delay, time);
    return t;
  }
  function timerFlush() {
    now(); // Get the current time, if not already set.

    ++frame; // Pretend weвЂ™ve set an alarm, if we havenвЂ™t already.

    var t = taskHead,
        e;

    while (t) {
      if ((e = clockNow - t._time) >= 0) t._call.call(null, e);
      t = t._next;
    }

    --frame;
  }

  function wake() {
    clockNow = (clockLast = clock.now()) + clockSkew;
    frame = timeout = 0;

    try {
      timerFlush();
    } finally {
      frame = 0;
      nap();
      clockNow = 0;
    }
  }

  function poke() {
    var now = clock.now(),
        delay = now - clockLast;
    if (delay > pokeDelay) clockSkew -= delay, clockLast = now;
  }

  function nap() {
    var t0,
        t1 = taskHead,
        t2,
        time = Infinity;

    while (t1) {
      if (t1._call) {
        if (time > t1._time) time = t1._time;
        t0 = t1, t1 = t1._next;
      } else {
        t2 = t1._next, t1._next = null;
        t1 = t0 ? t0._next = t2 : taskHead = t2;
      }
    }

    taskTail = t0;
    sleep(time);
  }

  function sleep(time) {
    if (frame) return; // Soonest alarm already set, or will be.

    if (timeout) timeout = clearTimeout(timeout);
    var delay = time - clockNow; // Strictly less than if we recomputed clockNow.

    if (delay > 24) {
      if (time < Infinity) timeout = setTimeout(wake, time - clock.now() - clockSkew);
      if (interval) interval = clearInterval(interval);
    } else {
      if (!interval) clockLast = clock.now(), interval = setInterval(poke, pokeDelay);
      frame = 1, setFrame(wake);
    }
  }

  function timeout$1 (callback, delay, time) {
    var t = new Timer();
    delay = delay == null ? 0 : +delay;
    t.restart(function (elapsed) {
      t.stop();
      callback(elapsed + delay);
    }, delay, time);
    return t;
  }

  function interval$1 (callback, delay, time) {
    var t = new Timer(),
        total = delay;
    if (delay == null) return t.restart(callback, delay, time), t;
    delay = +delay, time = time == null ? now() : +time;
    t.restart(function tick(elapsed) {
      elapsed += total;
      t.restart(tick, total += delay, time);
      callback(elapsed);
    }, delay, time);
    return t;
  }

  var emptyOn = dispatch("start", "end", "cancel", "interrupt");
  var emptyTween = [];
  var CREATED = 0;
  var SCHEDULED = 1;
  var STARTING = 2;
  var STARTED = 3;
  var RUNNING = 4;
  var ENDING = 5;
  var ENDED = 6;
  function schedule (node, name, id, index, group, timing) {
    var schedules = node.__transition;
    if (!schedules) node.__transition = {};else if (id in schedules) return;
    create$1(node, id, {
      name: name,
      index: index,
      // For context during callback.
      group: group,
      // For context during callback.
      on: emptyOn,
      tween: emptyTween,
      time: timing.time,
      delay: timing.delay,
      duration: timing.duration,
      ease: timing.ease,
      timer: null,
      state: CREATED
    });
  }
  function init(node, id) {
    var schedule = get$1(node, id);
    if (schedule.state > CREATED) throw new Error("too late; already scheduled");
    return schedule;
  }
  function set$1(node, id) {
    var schedule = get$1(node, id);
    if (schedule.state > STARTED) throw new Error("too late; already running");
    return schedule;
  }
  function get$1(node, id) {
    var schedule = node.__transition;
    if (!schedule || !(schedule = schedule[id])) throw new Error("transition not found");
    return schedule;
  }

  function create$1(node, id, self) {
    var schedules = node.__transition,
        tween; // Initialize the self timer when the transition is created.
    // Note the actual delay is not known until the first callback!

    schedules[id] = self;
    self.timer = timer(schedule, 0, self.time);

    function schedule(elapsed) {
      self.state = SCHEDULED;
      self.timer.restart(start, self.delay, self.time); // If the elapsed delay is less than our first sleep, start immediately.

      if (self.delay <= elapsed) start(elapsed - self.delay);
    }

    function start(elapsed) {
      var i, j, n, o; // If the state is not SCHEDULED, then we previously errored on start.

      if (self.state !== SCHEDULED) return stop();

      for (i in schedules) {
        o = schedules[i];
        if (o.name !== self.name) continue; // While this element already has a starting transition during this frame,
        // defer starting an interrupting transition until that transition has a
        // chance to tick (and possibly end); see d3/d3-transition#54!

        if (o.state === STARTED) return timeout$1(start); // Interrupt the active transition, if any.

        if (o.state === RUNNING) {
          o.state = ENDED;
          o.timer.stop();
          o.on.call("interrupt", node, node.__data__, o.index, o.group);
          delete schedules[i];
        } // Cancel any pre-empted transitions.
        else if (+i < id) {
            o.state = ENDED;
            o.timer.stop();
            o.on.call("cancel", node, node.__data__, o.index, o.group);
            delete schedules[i];
          }
      } // Defer the first tick to end of the current frame; see d3/d3#1576.
      // Note the transition may be canceled after start and before the first tick!
      // Note this must be scheduled before the start event; see d3/d3-transition#16!
      // Assuming this is successful, subsequent callbacks go straight to tick.


      timeout$1(function () {
        if (self.state === STARTED) {
          self.state = RUNNING;
          self.timer.restart(tick, self.delay, self.time);
          tick(elapsed);
        }
      }); // Dispatch the start event.
      // Note this must be done before the tween are initialized.

      self.state = STARTING;
      self.on.call("start", node, node.__data__, self.index, self.group);
      if (self.state !== STARTING) return; // interrupted

      self.state = STARTED; // Initialize the tween, deleting null tween.

      tween = new Array(n = self.tween.length);

      for (i = 0, j = -1; i < n; ++i) {
        if (o = self.tween[i].value.call(node, node.__data__, self.index, self.group)) {
          tween[++j] = o;
        }
      }

      tween.length = j + 1;
    }

    function tick(elapsed) {
      var t = elapsed < self.duration ? self.ease.call(null, elapsed / self.duration) : (self.timer.restart(stop), self.state = ENDING, 1),
          i = -1,
          n = tween.length;

      while (++i < n) {
        tween[i].call(node, t);
      } // Dispatch the end event.


      if (self.state === ENDING) {
        self.on.call("end", node, node.__data__, self.index, self.group);
        stop();
      }
    }

    function stop() {
      self.state = ENDED;
      self.timer.stop();
      delete schedules[id];

      for (var i in schedules) {
        return;
      } // eslint-disable-line no-unused-vars


      delete node.__transition;
    }
  }

  function interrupt (node, name) {
    var schedules = node.__transition,
        schedule$$1,
        active,
        empty = true,
        i;
    if (!schedules) return;
    name = name == null ? null : name + "";

    for (i in schedules) {
      if ((schedule$$1 = schedules[i]).name !== name) {
        empty = false;
        continue;
      }

      active = schedule$$1.state > STARTING && schedule$$1.state < ENDING;
      schedule$$1.state = ENDED;
      schedule$$1.timer.stop();
      schedule$$1.on.call(active ? "interrupt" : "cancel", node, node.__data__, schedule$$1.index, schedule$$1.group);
      delete schedules[i];
    }

    if (empty) delete node.__transition;
  }

  function selection_interrupt (name) {
    return this.each(function () {
      interrupt(this, name);
    });
  }

  function tweenRemove(id, name) {
    var tween0, tween1;
    return function () {
      var schedule$$1 = set$1(this, id),
          tween = schedule$$1.tween; // If this node shared tween with the previous node,
      // just assign the updated shared tween and weвЂ™re done!
      // Otherwise, copy-on-write.

      if (tween !== tween0) {
        tween1 = tween0 = tween;

        for (var i = 0, n = tween1.length; i < n; ++i) {
          if (tween1[i].name === name) {
            tween1 = tween1.slice();
            tween1.splice(i, 1);
            break;
          }
        }
      }

      schedule$$1.tween = tween1;
    };
  }

  function tweenFunction(id, name, value) {
    var tween0, tween1;
    if (typeof value !== "function") throw new Error();
    return function () {
      var schedule$$1 = set$1(this, id),
          tween = schedule$$1.tween; // If this node shared tween with the previous node,
      // just assign the updated shared tween and weвЂ™re done!
      // Otherwise, copy-on-write.

      if (tween !== tween0) {
        tween1 = (tween0 = tween).slice();

        for (var t = {
          name: name,
          value: value
        }, i = 0, n = tween1.length; i < n; ++i) {
          if (tween1[i].name === name) {
            tween1[i] = t;
            break;
          }
        }

        if (i === n) tween1.push(t);
      }

      schedule$$1.tween = tween1;
    };
  }

  function transition_tween (name, value) {
    var id = this._id;
    name += "";

    if (arguments.length < 2) {
      var tween = get$1(this.node(), id).tween;

      for (var i = 0, n = tween.length, t; i < n; ++i) {
        if ((t = tween[i]).name === name) {
          return t.value;
        }
      }

      return null;
    }

    return this.each((value == null ? tweenRemove : tweenFunction)(id, name, value));
  }
  function tweenValue(transition, name, value) {
    var id = transition._id;
    transition.each(function () {
      var schedule$$1 = set$1(this, id);
      (schedule$$1.value || (schedule$$1.value = {}))[name] = value.apply(this, arguments);
    });
    return function (node) {
      return get$1(node, id).value[name];
    };
  }

  function interpolate (a, b) {
    var c;
    return (typeof b === "number" ? interpolateNumber : b instanceof color ? interpolateRgb : (c = color(b)) ? (b = c, interpolateRgb) : interpolateString)(a, b);
  }

  function attrRemove$1(name) {
    return function () {
      this.removeAttribute(name);
    };
  }

  function attrRemoveNS$1(fullname) {
    return function () {
      this.removeAttributeNS(fullname.space, fullname.local);
    };
  }

  function attrConstant$1(name, interpolate$$1, value1) {
    var string00,
        string1 = value1 + "",
        interpolate0;
    return function () {
      var string0 = this.getAttribute(name);
      return string0 === string1 ? null : string0 === string00 ? interpolate0 : interpolate0 = interpolate$$1(string00 = string0, value1);
    };
  }

  function attrConstantNS$1(fullname, interpolate$$1, value1) {
    var string00,
        string1 = value1 + "",
        interpolate0;
    return function () {
      var string0 = this.getAttributeNS(fullname.space, fullname.local);
      return string0 === string1 ? null : string0 === string00 ? interpolate0 : interpolate0 = interpolate$$1(string00 = string0, value1);
    };
  }

  function attrFunction$1(name, interpolate$$1, value) {
    var string00, string10, interpolate0;
    return function () {
      var string0,
          value1 = value(this),
          string1;
      if (value1 == null) return void this.removeAttribute(name);
      string0 = this.getAttribute(name);
      string1 = value1 + "";
      return string0 === string1 ? null : string0 === string00 && string1 === string10 ? interpolate0 : (string10 = string1, interpolate0 = interpolate$$1(string00 = string0, value1));
    };
  }

  function attrFunctionNS$1(fullname, interpolate$$1, value) {
    var string00, string10, interpolate0;
    return function () {
      var string0,
          value1 = value(this),
          string1;
      if (value1 == null) return void this.removeAttributeNS(fullname.space, fullname.local);
      string0 = this.getAttributeNS(fullname.space, fullname.local);
      string1 = value1 + "";
      return string0 === string1 ? null : string0 === string00 && string1 === string10 ? interpolate0 : (string10 = string1, interpolate0 = interpolate$$1(string00 = string0, value1));
    };
  }

  function transition_attr (name, value) {
    var fullname = namespace(name),
        i = fullname === "transform" ? interpolateTransformSvg : interpolate;
    return this.attrTween(name, typeof value === "function" ? (fullname.local ? attrFunctionNS$1 : attrFunction$1)(fullname, i, tweenValue(this, "attr." + name, value)) : value == null ? (fullname.local ? attrRemoveNS$1 : attrRemove$1)(fullname) : (fullname.local ? attrConstantNS$1 : attrConstant$1)(fullname, i, value));
  }

  function attrInterpolate(name, i) {
    return function (t) {
      this.setAttribute(name, i(t));
    };
  }

  function attrInterpolateNS(fullname, i) {
    return function (t) {
      this.setAttributeNS(fullname.space, fullname.local, i(t));
    };
  }

  function attrTweenNS(fullname, value) {
    var t0, i0;

    function tween() {
      var i = value.apply(this, arguments);
      if (i !== i0) t0 = (i0 = i) && attrInterpolateNS(fullname, i);
      return t0;
    }

    tween._value = value;
    return tween;
  }

  function attrTween(name, value) {
    var t0, i0;

    function tween() {
      var i = value.apply(this, arguments);
      if (i !== i0) t0 = (i0 = i) && attrInterpolate(name, i);
      return t0;
    }

    tween._value = value;
    return tween;
  }

  function transition_attrTween (name, value) {
    var key = "attr." + name;
    if (arguments.length < 2) return (key = this.tween(key)) && key._value;
    if (value == null) return this.tween(key, null);
    if (typeof value !== "function") throw new Error();
    var fullname = namespace(name);
    return this.tween(key, (fullname.local ? attrTweenNS : attrTween)(fullname, value));
  }

  function delayFunction(id, value) {
    return function () {
      init(this, id).delay = +value.apply(this, arguments);
    };
  }

  function delayConstant(id, value) {
    return value = +value, function () {
      init(this, id).delay = value;
    };
  }

  function transition_delay (value) {
    var id = this._id;
    return arguments.length ? this.each((typeof value === "function" ? delayFunction : delayConstant)(id, value)) : get$1(this.node(), id).delay;
  }

  function durationFunction(id, value) {
    return function () {
      set$1(this, id).duration = +value.apply(this, arguments);
    };
  }

  function durationConstant(id, value) {
    return value = +value, function () {
      set$1(this, id).duration = value;
    };
  }

  function transition_duration (value) {
    var id = this._id;
    return arguments.length ? this.each((typeof value === "function" ? durationFunction : durationConstant)(id, value)) : get$1(this.node(), id).duration;
  }

  function easeConstant(id, value) {
    if (typeof value !== "function") throw new Error();
    return function () {
      set$1(this, id).ease = value;
    };
  }

  function transition_ease (value) {
    var id = this._id;
    return arguments.length ? this.each(easeConstant(id, value)) : get$1(this.node(), id).ease;
  }

  function transition_filter (match) {
    if (typeof match !== "function") match = matcher(match);

    for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, subgroup = subgroups[j] = [], node, i = 0; i < n; ++i) {
        if ((node = group[i]) && match.call(node, node.__data__, i, group)) {
          subgroup.push(node);
        }
      }
    }

    return new Transition(subgroups, this._parents, this._name, this._id);
  }

  function transition_merge (transition$$1) {
    if (transition$$1._id !== this._id) throw new Error();

    for (var groups0 = this._groups, groups1 = transition$$1._groups, m0 = groups0.length, m1 = groups1.length, m = Math.min(m0, m1), merges = new Array(m0), j = 0; j < m; ++j) {
      for (var group0 = groups0[j], group1 = groups1[j], n = group0.length, merge = merges[j] = new Array(n), node, i = 0; i < n; ++i) {
        if (node = group0[i] || group1[i]) {
          merge[i] = node;
        }
      }
    }

    for (; j < m0; ++j) {
      merges[j] = groups0[j];
    }

    return new Transition(merges, this._parents, this._name, this._id);
  }

  function start(name) {
    return (name + "").trim().split(/^|\s+/).every(function (t) {
      var i = t.indexOf(".");
      if (i >= 0) t = t.slice(0, i);
      return !t || t === "start";
    });
  }

  function onFunction(id, name, listener) {
    var on0,
        on1,
        sit = start(name) ? init : set$1;
    return function () {
      var schedule$$1 = sit(this, id),
          on = schedule$$1.on; // If this node shared a dispatch with the previous node,
      // just assign the updated shared dispatch and weвЂ™re done!
      // Otherwise, copy-on-write.

      if (on !== on0) (on1 = (on0 = on).copy()).on(name, listener);
      schedule$$1.on = on1;
    };
  }

  function transition_on (name, listener) {
    var id = this._id;
    return arguments.length < 2 ? get$1(this.node(), id).on.on(name) : this.each(onFunction(id, name, listener));
  }

  function removeFunction(id) {
    return function () {
      var parent = this.parentNode;

      for (var i in this.__transition) {
        if (+i !== id) return;
      }

      if (parent) parent.removeChild(this);
    };
  }

  function transition_remove () {
    return this.on("end.remove", removeFunction(this._id));
  }

  function transition_select (select$$1) {
    var name = this._name,
        id = this._id;
    if (typeof select$$1 !== "function") select$$1 = selector(select$$1);

    for (var groups = this._groups, m = groups.length, subgroups = new Array(m), j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, subgroup = subgroups[j] = new Array(n), node, subnode, i = 0; i < n; ++i) {
        if ((node = group[i]) && (subnode = select$$1.call(node, node.__data__, i, group))) {
          if ("__data__" in node) subnode.__data__ = node.__data__;
          subgroup[i] = subnode;
          schedule(subgroup[i], name, id, i, subgroup, get$1(node, id));
        }
      }
    }

    return new Transition(subgroups, this._parents, name, id);
  }

  function transition_selectAll (select$$1) {
    var name = this._name,
        id = this._id;
    if (typeof select$$1 !== "function") select$$1 = selectorAll(select$$1);

    for (var groups = this._groups, m = groups.length, subgroups = [], parents = [], j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
        if (node = group[i]) {
          for (var children = select$$1.call(node, node.__data__, i, group), child, inherit = get$1(node, id), k = 0, l = children.length; k < l; ++k) {
            if (child = children[k]) {
              schedule(child, name, id, k, children, inherit);
            }
          }

          subgroups.push(children);
          parents.push(node);
        }
      }
    }

    return new Transition(subgroups, parents, name, id);
  }

  var Selection$1 = selection.prototype.constructor;
  function transition_selection () {
    return new Selection$1(this._groups, this._parents);
  }

  function styleNull(name, interpolate$$1) {
    var string00, string10, interpolate0;
    return function () {
      var string0 = styleValue(this, name),
          string1 = (this.style.removeProperty(name), styleValue(this, name));
      return string0 === string1 ? null : string0 === string00 && string1 === string10 ? interpolate0 : interpolate0 = interpolate$$1(string00 = string0, string10 = string1);
    };
  }

  function styleRemove$1(name) {
    return function () {
      this.style.removeProperty(name);
    };
  }

  function styleConstant$1(name, interpolate$$1, value1) {
    var string00,
        string1 = value1 + "",
        interpolate0;
    return function () {
      var string0 = styleValue(this, name);
      return string0 === string1 ? null : string0 === string00 ? interpolate0 : interpolate0 = interpolate$$1(string00 = string0, value1);
    };
  }

  function styleFunction$1(name, interpolate$$1, value) {
    var string00, string10, interpolate0;
    return function () {
      var string0 = styleValue(this, name),
          value1 = value(this),
          string1 = value1 + "";
      if (value1 == null) string1 = value1 = (this.style.removeProperty(name), styleValue(this, name));
      return string0 === string1 ? null : string0 === string00 && string1 === string10 ? interpolate0 : (string10 = string1, interpolate0 = interpolate$$1(string00 = string0, value1));
    };
  }

  function styleMaybeRemove(id, name) {
    var on0,
        on1,
        listener0,
        key = "style." + name,
        event = "end." + key,
        remove;
    return function () {
      var schedule$$1 = set$1(this, id),
          on = schedule$$1.on,
          listener = schedule$$1.value[key] == null ? remove || (remove = styleRemove$1(name)) : undefined; // If this node shared a dispatch with the previous node,
      // just assign the updated shared dispatch and weвЂ™re done!
      // Otherwise, copy-on-write.

      if (on !== on0 || listener0 !== listener) (on1 = (on0 = on).copy()).on(event, listener0 = listener);
      schedule$$1.on = on1;
    };
  }

  function transition_style (name, value, priority) {
    var i = (name += "") === "transform" ? interpolateTransformCss : interpolate;
    return value == null ? this.styleTween(name, styleNull(name, i)).on("end.style." + name, styleRemove$1(name)) : typeof value === "function" ? this.styleTween(name, styleFunction$1(name, i, tweenValue(this, "style." + name, value))).each(styleMaybeRemove(this._id, name)) : this.styleTween(name, styleConstant$1(name, i, value), priority).on("end.style." + name, null);
  }

  function styleInterpolate(name, i, priority) {
    return function (t) {
      this.style.setProperty(name, i(t), priority);
    };
  }

  function styleTween(name, value, priority) {
    var t, i0;

    function tween() {
      var i = value.apply(this, arguments);
      if (i !== i0) t = (i0 = i) && styleInterpolate(name, i, priority);
      return t;
    }

    tween._value = value;
    return tween;
  }

  function transition_styleTween (name, value, priority) {
    var key = "style." + (name += "");
    if (arguments.length < 2) return (key = this.tween(key)) && key._value;
    if (value == null) return this.tween(key, null);
    if (typeof value !== "function") throw new Error();
    return this.tween(key, styleTween(name, value, priority == null ? "" : priority));
  }

  function textConstant$1(value) {
    return function () {
      this.textContent = value;
    };
  }

  function textFunction$1(value) {
    return function () {
      var value1 = value(this);
      this.textContent = value1 == null ? "" : value1;
    };
  }

  function transition_text (value) {
    return this.tween("text", typeof value === "function" ? textFunction$1(tweenValue(this, "text", value)) : textConstant$1(value == null ? "" : value + ""));
  }

  function transition_transition () {
    var name = this._name,
        id0 = this._id,
        id1 = newId();

    for (var groups = this._groups, m = groups.length, j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
        if (node = group[i]) {
          var inherit = get$1(node, id0);
          schedule(node, name, id1, i, group, {
            time: inherit.time + inherit.delay + inherit.duration,
            delay: 0,
            duration: inherit.duration,
            ease: inherit.ease
          });
        }
      }
    }

    return new Transition(groups, this._parents, name, id1);
  }

  function transition_end () {
    var on0,
        on1,
        that = this,
        id = that._id,
        size = that.size();
    return new Promise(function (resolve, reject) {
      var cancel = {
        value: reject
      },
          end = {
        value: function value() {
          if (--size === 0) resolve();
        }
      };
      that.each(function () {
        var schedule$$1 = set$1(this, id),
            on = schedule$$1.on; // If this node shared a dispatch with the previous node,
        // just assign the updated shared dispatch and weвЂ™re done!
        // Otherwise, copy-on-write.

        if (on !== on0) {
          on1 = (on0 = on).copy();

          on1._.cancel.push(cancel);

          on1._.interrupt.push(cancel);

          on1._.end.push(end);
        }

        schedule$$1.on = on1;
      });
    });
  }

  var id = 0;
  function Transition(groups, parents, name, id) {
    this._groups = groups;
    this._parents = parents;
    this._name = name;
    this._id = id;
  }
  function transition(name) {
    return selection().transition(name);
  }
  function newId() {
    return ++id;
  }
  var selection_prototype = selection.prototype;
  Transition.prototype = transition.prototype = {
    constructor: Transition,
    select: transition_select,
    selectAll: transition_selectAll,
    filter: transition_filter,
    merge: transition_merge,
    selection: transition_selection,
    transition: transition_transition,
    call: selection_prototype.call,
    nodes: selection_prototype.nodes,
    node: selection_prototype.node,
    size: selection_prototype.size,
    empty: selection_prototype.empty,
    each: selection_prototype.each,
    on: transition_on,
    attr: transition_attr,
    attrTween: transition_attrTween,
    style: transition_style,
    styleTween: transition_styleTween,
    text: transition_text,
    remove: transition_remove,
    tween: transition_tween,
    delay: transition_delay,
    duration: transition_duration,
    ease: transition_ease,
    end: transition_end
  };

  function linear$1(t) {
    return +t;
  }

  function quadIn(t) {
    return t * t;
  }
  function quadOut(t) {
    return t * (2 - t);
  }
  function quadInOut(t) {
    return ((t *= 2) <= 1 ? t * t : --t * (2 - t) + 1) / 2;
  }

  function cubicIn(t) {
    return t * t * t;
  }
  function cubicOut(t) {
    return --t * t * t + 1;
  }
  function cubicInOut(t) {
    return ((t *= 2) <= 1 ? t * t * t : (t -= 2) * t * t + 2) / 2;
  }

  var exponent = 3;
  var polyIn = function custom(e) {
    e = +e;

    function polyIn(t) {
      return Math.pow(t, e);
    }

    polyIn.exponent = custom;
    return polyIn;
  }(exponent);
  var polyOut = function custom(e) {
    e = +e;

    function polyOut(t) {
      return 1 - Math.pow(1 - t, e);
    }

    polyOut.exponent = custom;
    return polyOut;
  }(exponent);
  var polyInOut = function custom(e) {
    e = +e;

    function polyInOut(t) {
      return ((t *= 2) <= 1 ? Math.pow(t, e) : 2 - Math.pow(2 - t, e)) / 2;
    }

    polyInOut.exponent = custom;
    return polyInOut;
  }(exponent);

  var pi = Math.PI,
      halfPi = pi / 2;
  function sinIn(t) {
    return 1 - Math.cos(t * halfPi);
  }
  function sinOut(t) {
    return Math.sin(t * halfPi);
  }
  function sinInOut(t) {
    return (1 - Math.cos(pi * t)) / 2;
  }

  function expIn(t) {
    return Math.pow(2, 10 * t - 10);
  }
  function expOut(t) {
    return 1 - Math.pow(2, -10 * t);
  }
  function expInOut(t) {
    return ((t *= 2) <= 1 ? Math.pow(2, 10 * t - 10) : 2 - Math.pow(2, 10 - 10 * t)) / 2;
  }

  function circleIn(t) {
    return 1 - Math.sqrt(1 - t * t);
  }
  function circleOut(t) {
    return Math.sqrt(1 - --t * t);
  }
  function circleInOut(t) {
    return ((t *= 2) <= 1 ? 1 - Math.sqrt(1 - t * t) : Math.sqrt(1 - (t -= 2) * t) + 1) / 2;
  }

  var b1 = 4 / 11,
      b2 = 6 / 11,
      b3 = 8 / 11,
      b4 = 3 / 4,
      b5 = 9 / 11,
      b6 = 10 / 11,
      b7 = 15 / 16,
      b8 = 21 / 22,
      b9 = 63 / 64,
      b0 = 1 / b1 / b1;
  function bounceIn(t) {
    return 1 - bounceOut(1 - t);
  }
  function bounceOut(t) {
    return (t = +t) < b1 ? b0 * t * t : t < b3 ? b0 * (t -= b2) * t + b4 : t < b6 ? b0 * (t -= b5) * t + b7 : b0 * (t -= b8) * t + b9;
  }
  function bounceInOut(t) {
    return ((t *= 2) <= 1 ? 1 - bounceOut(1 - t) : bounceOut(t - 1) + 1) / 2;
  }

  var overshoot = 1.70158;
  var backIn = function custom(s) {
    s = +s;

    function backIn(t) {
      return t * t * ((s + 1) * t - s);
    }

    backIn.overshoot = custom;
    return backIn;
  }(overshoot);
  var backOut = function custom(s) {
    s = +s;

    function backOut(t) {
      return --t * t * ((s + 1) * t + s) + 1;
    }

    backOut.overshoot = custom;
    return backOut;
  }(overshoot);
  var backInOut = function custom(s) {
    s = +s;

    function backInOut(t) {
      return ((t *= 2) < 1 ? t * t * ((s + 1) * t - s) : (t -= 2) * t * ((s + 1) * t + s) + 2) / 2;
    }

    backInOut.overshoot = custom;
    return backInOut;
  }(overshoot);

  var tau = 2 * Math.PI,
      amplitude = 1,
      period = 0.3;
  var elasticIn = function custom(a, p) {
    var s = Math.asin(1 / (a = Math.max(1, a))) * (p /= tau);

    function elasticIn(t) {
      return a * Math.pow(2, 10 * --t) * Math.sin((s - t) / p);
    }

    elasticIn.amplitude = function (a) {
      return custom(a, p * tau);
    };

    elasticIn.period = function (p) {
      return custom(a, p);
    };

    return elasticIn;
  }(amplitude, period);
  var elasticOut = function custom(a, p) {
    var s = Math.asin(1 / (a = Math.max(1, a))) * (p /= tau);

    function elasticOut(t) {
      return 1 - a * Math.pow(2, -10 * (t = +t)) * Math.sin((t + s) / p);
    }

    elasticOut.amplitude = function (a) {
      return custom(a, p * tau);
    };

    elasticOut.period = function (p) {
      return custom(a, p);
    };

    return elasticOut;
  }(amplitude, period);
  var elasticInOut = function custom(a, p) {
    var s = Math.asin(1 / (a = Math.max(1, a))) * (p /= tau);

    function elasticInOut(t) {
      return ((t = t * 2 - 1) < 0 ? a * Math.pow(2, 10 * t) * Math.sin((s - t) / p) : 2 - a * Math.pow(2, -10 * t) * Math.sin((s + t) / p)) / 2;
    }

    elasticInOut.amplitude = function (a) {
      return custom(a, p * tau);
    };

    elasticInOut.period = function (p) {
      return custom(a, p);
    };

    return elasticInOut;
  }(amplitude, period);

  var defaultTiming = {
    time: null,
    // Set on use.
    delay: 0,
    duration: 250,
    ease: cubicInOut
  };

  function inherit(node, id) {
    var timing;

    while (!(timing = node.__transition) || !(timing = timing[id])) {
      if (!(node = node.parentNode)) {
        return defaultTiming.time = now(), defaultTiming;
      }
    }

    return timing;
  }

  function selection_transition (name) {
    var id, timing;

    if (name instanceof Transition) {
      id = name._id, name = name._name;
    } else {
      id = newId(), (timing = defaultTiming).time = now(), name = name == null ? null : name + "";
    }

    for (var groups = this._groups, m = groups.length, j = 0; j < m; ++j) {
      for (var group = groups[j], n = group.length, node, i = 0; i < n; ++i) {
        if (node = group[i]) {
          schedule(node, name, id, i, group, timing || inherit(node, id));
        }
      }
    }

    return new Transition(groups, this._parents, name, id);
  }

  selection.prototype.interrupt = selection_interrupt;
  selection.prototype.transition = selection_transition;

  var root$1 = [null];
  function active (node, name) {
    var schedules = node.__transition,
        schedule$$1,
        i;

    if (schedules) {
      name = name == null ? null : name + "";

      for (i in schedules) {
        if ((schedule$$1 = schedules[i]).state > SCHEDULED && schedule$$1.name === name) {
          return new Transition([[node]], root$1, name, +i);
        }
      }
    }

    return null;
  }

  function constant$4 (x) {
    return function () {
      return x;
    };
  }

  function BrushEvent (target, type, selection) {
    this.target = target;
    this.type = type;
    this.selection = selection;
  }

  function nopropagation$1() {
    exports.event.stopImmediatePropagation();
  }
  function noevent$1 () {
    exports.event.preventDefault();
    exports.event.stopImmediatePropagation();
  }

  var MODE_DRAG = {
    name: "drag"
  },
      MODE_SPACE = {
    name: "space"
  },
      MODE_HANDLE = {
    name: "handle"
  },
      MODE_CENTER = {
    name: "center"
  };
  var X = {
    name: "x",
    handles: ["e", "w"].map(type),
    input: function input(x, e) {
      return x && [[x[0], e[0][1]], [x[1], e[1][1]]];
    },
    output: function output(xy) {
      return xy && [xy[0][0], xy[1][0]];
    }
  };
  var Y = {
    name: "y",
    handles: ["n", "s"].map(type),
    input: function input(y, e) {
      return y && [[e[0][0], y[0]], [e[1][0], y[1]]];
    },
    output: function output(xy) {
      return xy && [xy[0][1], xy[1][1]];
    }
  };
  var XY = {
    name: "xy",
    handles: ["n", "e", "s", "w", "nw", "ne", "se", "sw"].map(type),
    input: function input(xy) {
      return xy;
    },
    output: function output(xy) {
      return xy;
    }
  };
  var cursors = {
    overlay: "crosshair",
    selection: "move",
    n: "ns-resize",
    e: "ew-resize",
    s: "ns-resize",
    w: "ew-resize",
    nw: "nwse-resize",
    ne: "nesw-resize",
    se: "nwse-resize",
    sw: "nesw-resize"
  };
  var flipX = {
    e: "w",
    w: "e",
    nw: "ne",
    ne: "nw",
    se: "sw",
    sw: "se"
  };
  var flipY = {
    n: "s",
    s: "n",
    nw: "sw",
    ne: "se",
    se: "ne",
    sw: "nw"
  };
  var signsX = {
    overlay: +1,
    selection: +1,
    n: null,
    e: +1,
    s: null,
    w: -1,
    nw: -1,
    ne: +1,
    se: +1,
    sw: -1
  };
  var signsY = {
    overlay: +1,
    selection: +1,
    n: -1,
    e: null,
    s: +1,
    w: null,
    nw: -1,
    ne: -1,
    se: +1,
    sw: +1
  };

  function type(t) {
    return {
      type: t
    };
  } // Ignore right-click, since that should open the context menu.


  function defaultFilter$1() {
    return !exports.event.button;
  }

  function defaultExtent() {
    var svg = this.ownerSVGElement || this;
    return [[0, 0], [svg.width.baseVal.value, svg.height.baseVal.value]];
  } // Like d3.local, but with the name вЂњ__brushвЂќ rather than auto-generated.


  function local$1(node) {
    while (!node.__brush) {
      if (!(node = node.parentNode)) return;
    }

    return node.__brush;
  }

  function empty$1(extent) {
    return extent[0][0] === extent[1][0] || extent[0][1] === extent[1][1];
  }

  function brushSelection(node) {
    var state = node.__brush;
    return state ? state.dim.output(state.selection) : null;
  }
  function brushX() {
    return brush$1(X);
  }
  function brushY() {
    return brush$1(Y);
  }
  function brush () {
    return brush$1(XY);
  }

  function brush$1(dim) {
    var extent = defaultExtent,
        filter = defaultFilter$1,
        listeners = dispatch(brush, "start", "brush", "end"),
        handleSize = 6,
        touchending;

    function brush(group) {
      var overlay = group.property("__brush", initialize).selectAll(".overlay").data([type("overlay")]);
      overlay.enter().append("rect").attr("class", "overlay").attr("pointer-events", "all").attr("cursor", cursors.overlay).merge(overlay).each(function () {
        var extent = local$1(this).extent;
        select(this).attr("x", extent[0][0]).attr("y", extent[0][1]).attr("width", extent[1][0] - extent[0][0]).attr("height", extent[1][1] - extent[0][1]);
      });
      group.selectAll(".selection").data([type("selection")]).enter().append("rect").attr("class", "selection").attr("cursor", cursors.selection).attr("fill", "#777").attr("fill-opacity", 0.3).attr("stroke", "#fff").attr("shape-rendering", "crispEdges");
      var handle = group.selectAll(".handle").data(dim.handles, function (d) {
        return d.type;
      });
      handle.exit().remove();
      handle.enter().append("rect").attr("class", function (d) {
        return "handle handle--" + d.type;
      }).attr("cursor", function (d) {
        return cursors[d.type];
      });
      group.each(redraw).attr("fill", "none").attr("pointer-events", "all").style("-webkit-tap-highlight-color", "rgba(0,0,0,0)").on("mousedown.brush touchstart.brush", started);
    }

    brush.move = function (group, selection$$1) {
      if (group.selection) {
        group.on("start.brush", function () {
          emitter(this, arguments).beforestart().start();
        }).on("interrupt.brush end.brush", function () {
          emitter(this, arguments).end();
        }).tween("brush", function () {
          var that = this,
              state = that.__brush,
              emit = emitter(that, arguments),
              selection0 = state.selection,
              selection1 = dim.input(typeof selection$$1 === "function" ? selection$$1.apply(this, arguments) : selection$$1, state.extent),
              i = interpolateValue(selection0, selection1);

          function tween(t) {
            state.selection = t === 1 && empty$1(selection1) ? null : i(t);
            redraw.call(that);
            emit.brush();
          }

          return selection0 && selection1 ? tween : tween(1);
        });
      } else {
        group.each(function () {
          var that = this,
              args = arguments,
              state = that.__brush,
              selection1 = dim.input(typeof selection$$1 === "function" ? selection$$1.apply(that, args) : selection$$1, state.extent),
              emit = emitter(that, args).beforestart();
          interrupt(that);
          state.selection = selection1 == null || empty$1(selection1) ? null : selection1;
          redraw.call(that);
          emit.start().brush().end();
        });
      }
    };

    function redraw() {
      var group = select(this),
          selection$$1 = local$1(this).selection;

      if (selection$$1) {
        group.selectAll(".selection").style("display", null).attr("x", selection$$1[0][0]).attr("y", selection$$1[0][1]).attr("width", selection$$1[1][0] - selection$$1[0][0]).attr("height", selection$$1[1][1] - selection$$1[0][1]);
        group.selectAll(".handle").style("display", null).attr("x", function (d) {
          return d.type[d.type.length - 1] === "e" ? selection$$1[1][0] - handleSize / 2 : selection$$1[0][0] - handleSize / 2;
        }).attr("y", function (d) {
          return d.type[0] === "s" ? selection$$1[1][1] - handleSize / 2 : selection$$1[0][1] - handleSize / 2;
        }).attr("width", function (d) {
          return d.type === "n" || d.type === "s" ? selection$$1[1][0] - selection$$1[0][0] + handleSize : handleSize;
        }).attr("height", function (d) {
          return d.type === "e" || d.type === "w" ? selection$$1[1][1] - selection$$1[0][1] + handleSize : handleSize;
        });
      } else {
        group.selectAll(".selection,.handle").style("display", "none").attr("x", null).attr("y", null).attr("width", null).attr("height", null);
      }
    }

    function emitter(that, args) {
      return that.__brush.emitter || new Emitter(that, args);
    }

    function Emitter(that, args) {
      this.that = that;
      this.args = args;
      this.state = that.__brush;
      this.active = 0;
    }

    Emitter.prototype = {
      beforestart: function beforestart() {
        if (++this.active === 1) this.state.emitter = this, this.starting = true;
        return this;
      },
      start: function start() {
        if (this.starting) this.starting = false, this.emit("start");
        return this;
      },
      brush: function brush() {
        this.emit("brush");
        return this;
      },
      end: function end() {
        if (--this.active === 0) delete this.state.emitter, this.emit("end");
        return this;
      },
      emit: function emit(type) {
        customEvent(new BrushEvent(brush, type, dim.output(this.state.selection)), listeners.apply, listeners, [type, this.that, this.args]);
      }
    };

    function started() {
      if (exports.event.touches) {
        if (exports.event.changedTouches.length < exports.event.touches.length) return noevent$1();
      } else if (touchending) return;

      if (!filter.apply(this, arguments)) return;
      var that = this,
          type = exports.event.target.__data__.type,
          mode = (exports.event.metaKey ? type = "overlay" : type) === "selection" ? MODE_DRAG : exports.event.altKey ? MODE_CENTER : MODE_HANDLE,
          signX = dim === Y ? null : signsX[type],
          signY = dim === X ? null : signsY[type],
          state = local$1(that),
          extent = state.extent,
          selection$$1 = state.selection,
          W = extent[0][0],
          w0,
          w1,
          N = extent[0][1],
          n0,
          n1,
          E = extent[1][0],
          e0,
          e1,
          S = extent[1][1],
          s0,
          s1,
          dx,
          dy,
          moving,
          shifting = signX && signY && exports.event.shiftKey,
          lockX,
          lockY,
          point0 = mouse(that),
          point$$1 = point0,
          emit = emitter(that, arguments).beforestart();

      if (type === "overlay") {
        state.selection = selection$$1 = [[w0 = dim === Y ? W : point0[0], n0 = dim === X ? N : point0[1]], [e0 = dim === Y ? E : w0, s0 = dim === X ? S : n0]];
      } else {
        w0 = selection$$1[0][0];
        n0 = selection$$1[0][1];
        e0 = selection$$1[1][0];
        s0 = selection$$1[1][1];
      }

      w1 = w0;
      n1 = n0;
      e1 = e0;
      s1 = s0;
      var group = select(that).attr("pointer-events", "none");
      var overlay = group.selectAll(".overlay").attr("cursor", cursors[type]);

      if (exports.event.touches) {
        group.on("touchmove.brush", moved, true).on("touchend.brush touchcancel.brush", ended, true);
      } else {
        var view = select(exports.event.view).on("keydown.brush", keydowned, true).on("keyup.brush", keyupped, true).on("mousemove.brush", moved, true).on("mouseup.brush", ended, true);
        dragDisable(exports.event.view);
      }

      nopropagation$1();
      interrupt(that);
      redraw.call(that);
      emit.start();

      function moved() {
        var point1 = mouse(that);

        if (shifting && !lockX && !lockY) {
          if (Math.abs(point1[0] - point$$1[0]) > Math.abs(point1[1] - point$$1[1])) lockY = true;else lockX = true;
        }

        point$$1 = point1;
        moving = true;
        noevent$1();
        move();
      }

      function move() {
        var t;
        dx = point$$1[0] - point0[0];
        dy = point$$1[1] - point0[1];

        switch (mode) {
          case MODE_SPACE:
          case MODE_DRAG:
            {
              if (signX) dx = Math.max(W - w0, Math.min(E - e0, dx)), w1 = w0 + dx, e1 = e0 + dx;
              if (signY) dy = Math.max(N - n0, Math.min(S - s0, dy)), n1 = n0 + dy, s1 = s0 + dy;
              break;
            }

          case MODE_HANDLE:
            {
              if (signX < 0) dx = Math.max(W - w0, Math.min(E - w0, dx)), w1 = w0 + dx, e1 = e0;else if (signX > 0) dx = Math.max(W - e0, Math.min(E - e0, dx)), w1 = w0, e1 = e0 + dx;
              if (signY < 0) dy = Math.max(N - n0, Math.min(S - n0, dy)), n1 = n0 + dy, s1 = s0;else if (signY > 0) dy = Math.max(N - s0, Math.min(S - s0, dy)), n1 = n0, s1 = s0 + dy;
              break;
            }

          case MODE_CENTER:
            {
              if (signX) w1 = Math.max(W, Math.min(E, w0 - dx * signX)), e1 = Math.max(W, Math.min(E, e0 + dx * signX));
              if (signY) n1 = Math.max(N, Math.min(S, n0 - dy * signY)), s1 = Math.max(N, Math.min(S, s0 + dy * signY));
              break;
            }
        }

        if (e1 < w1) {
          signX *= -1;
          t = w0, w0 = e0, e0 = t;
          t = w1, w1 = e1, e1 = t;
          if (type in flipX) overlay.attr("cursor", cursors[type = flipX[type]]);
        }

        if (s1 < n1) {
          signY *= -1;
          t = n0, n0 = s0, s0 = t;
          t = n1, n1 = s1, s1 = t;
          if (type in flipY) overlay.attr("cursor", cursors[type = flipY[type]]);
        }

        if (state.selection) selection$$1 = state.selection; // May be set by brush.move!

        if (lockX) w1 = selection$$1[0][0], e1 = selection$$1[1][0];
        if (lockY) n1 = selection$$1[0][1], s1 = selection$$1[1][1];

        if (selection$$1[0][0] !== w1 || selection$$1[0][1] !== n1 || selection$$1[1][0] !== e1 || selection$$1[1][1] !== s1) {
          state.selection = [[w1, n1], [e1, s1]];
          redraw.call(that);
          emit.brush();
        }
      }

      function ended() {
        nopropagation$1();

        if (exports.event.touches) {
          if (exports.event.touches.length) return;
          if (touchending) clearTimeout(touchending);
          touchending = setTimeout(function () {
            touchending = null;
          }, 500); // Ghost clicks are delayed!

          group.on("touchmove.brush touchend.brush touchcancel.brush", null);
        } else {
          yesdrag(exports.event.view, moving);
          view.on("keydown.brush keyup.brush mousemove.brush mouseup.brush", null);
        }

        group.attr("pointer-events", "all");
        overlay.attr("cursor", cursors.overlay);
        if (state.selection) selection$$1 = state.selection; // May be set by brush.move (on start)!

        if (empty$1(selection$$1)) state.selection = null, redraw.call(that);
        emit.end();
      }

      function keydowned() {
        switch (exports.event.keyCode) {
          case 16:
            {
              // SHIFT
              shifting = signX && signY;
              break;
            }

          case 18:
            {
              // ALT
              if (mode === MODE_HANDLE) {
                if (signX) e0 = e1 - dx * signX, w0 = w1 + dx * signX;
                if (signY) s0 = s1 - dy * signY, n0 = n1 + dy * signY;
                mode = MODE_CENTER;
                move();
              }

              break;
            }

          case 32:
            {
              // SPACE; takes priority over ALT
              if (mode === MODE_HANDLE || mode === MODE_CENTER) {
                if (signX < 0) e0 = e1 - dx;else if (signX > 0) w0 = w1 - dx;
                if (signY < 0) s0 = s1 - dy;else if (signY > 0) n0 = n1 - dy;
                mode = MODE_SPACE;
                overlay.attr("cursor", cursors.selection);
                move();
              }

              break;
            }

          default:
            return;
        }

        noevent$1();
      }

      function keyupped() {
        switch (exports.event.keyCode) {
          case 16:
            {
              // SHIFT
              if (shifting) {
                lockX = lockY = shifting = false;
                move();
              }

              break;
            }

          case 18:
            {
              // ALT
              if (mode === MODE_CENTER) {
                if (signX < 0) e0 = e1;else if (signX > 0) w0 = w1;
                if (signY < 0) s0 = s1;else if (signY > 0) n0 = n1;
                mode = MODE_HANDLE;
                move();
              }

              break;
            }

          case 32:
            {
              // SPACE
              if (mode === MODE_SPACE) {
                if (exports.event.altKey) {
                  if (signX) e0 = e1 - dx * signX, w0 = w1 + dx * signX;
                  if (signY) s0 = s1 - dy * signY, n0 = n1 + dy * signY;
                  mode = MODE_CENTER;
                } else {
                  if (signX < 0) e0 = e1;else if (signX > 0) w0 = w1;
                  if (signY < 0) s0 = s1;else if (signY > 0) n0 = n1;
                  mode = MODE_HANDLE;
                }

                overlay.attr("cursor", cursors[type]);
                move();
              }

              break;
            }

          default:
            return;
        }

        noevent$1();
      }
    }

    function initialize() {
      var state = this.__brush || {
        selection: null
      };
      state.extent = extent.apply(this, arguments);
      state.dim = dim;
      return state;
    }

    brush.extent = function (_) {
      return arguments.length ? (extent = typeof _ === "function" ? _ : constant$4([[+_[0][0], +_[0][1]], [+_[1][0], +_[1][1]]]), brush) : extent;
    };

    brush.filter = function (_) {
      return arguments.length ? (filter = typeof _ === "function" ? _ : constant$4(!!_), brush) : filter;
    };

    brush.handleSize = function (_) {
      return arguments.length ? (handleSize = +_, brush) : handleSize;
    };

    brush.on = function () {
      var value = listeners.on.apply(listeners, arguments);
      return value === listeners ? brush : value;
    };

    return brush;
  }

  var cos = Math.cos;
  var sin = Math.sin;
  var pi$1 = Math.PI;
  var halfPi$1 = pi$1 / 2;
  var tau$1 = pi$1 * 2;
  var max$1 = Math.max;

  function compareValue(compare) {
    return function (a, b) {
      return compare(a.source.value + a.target.value, b.source.value + b.target.value);
    };
  }

  function chord () {
    var padAngle = 0,
        sortGroups = null,
        sortSubgroups = null,
        sortChords = null;

    function chord(matrix) {
      var n = matrix.length,
          groupSums = [],
          groupIndex = sequence(n),
          subgroupIndex = [],
          chords = [],
          groups = chords.groups = new Array(n),
          subgroups = new Array(n * n),
          k,
          x,
          x0,
          dx,
          i,
          j; // Compute the sum.

      k = 0, i = -1;

      while (++i < n) {
        x = 0, j = -1;

        while (++j < n) {
          x += matrix[i][j];
        }

        groupSums.push(x);
        subgroupIndex.push(sequence(n));
        k += x;
      } // Sort groupsвЂ¦


      if (sortGroups) groupIndex.sort(function (a, b) {
        return sortGroups(groupSums[a], groupSums[b]);
      }); // Sort subgroupsвЂ¦

      if (sortSubgroups) subgroupIndex.forEach(function (d, i) {
        d.sort(function (a, b) {
          return sortSubgroups(matrix[i][a], matrix[i][b]);
        });
      }); // Convert the sum to scaling factor for [0, 2pi].
      // TODO Allow start and end angle to be specified?
      // TODO Allow padding to be specified as percentage?

      k = max$1(0, tau$1 - padAngle * n) / k;
      dx = k ? padAngle : tau$1 / n; // Compute the start and end angle for each group and subgroup.
      // Note: Opera has a bug reordering object literal properties!

      x = 0, i = -1;

      while (++i < n) {
        x0 = x, j = -1;

        while (++j < n) {
          var di = groupIndex[i],
              dj = subgroupIndex[di][j],
              v = matrix[di][dj],
              a0 = x,
              a1 = x += v * k;
          subgroups[dj * n + di] = {
            index: di,
            subindex: dj,
            startAngle: a0,
            endAngle: a1,
            value: v
          };
        }

        groups[di] = {
          index: di,
          startAngle: x0,
          endAngle: x,
          value: groupSums[di]
        };
        x += dx;
      } // Generate chords for each (non-empty) subgroup-subgroup link.


      i = -1;

      while (++i < n) {
        j = i - 1;

        while (++j < n) {
          var source = subgroups[j * n + i],
              target = subgroups[i * n + j];

          if (source.value || target.value) {
            chords.push(source.value < target.value ? {
              source: target,
              target: source
            } : {
              source: source,
              target: target
            });
          }
        }
      }

      return sortChords ? chords.sort(sortChords) : chords;
    }

    chord.padAngle = function (_) {
      return arguments.length ? (padAngle = max$1(0, _), chord) : padAngle;
    };

    chord.sortGroups = function (_) {
      return arguments.length ? (sortGroups = _, chord) : sortGroups;
    };

    chord.sortSubgroups = function (_) {
      return arguments.length ? (sortSubgroups = _, chord) : sortSubgroups;
    };

    chord.sortChords = function (_) {
      return arguments.length ? (_ == null ? sortChords = null : (sortChords = compareValue(_))._ = _, chord) : sortChords && sortChords._;
    };

    return chord;
  }

  var slice$2 = Array.prototype.slice;

  function constant$5 (x) {
    return function () {
      return x;
    };
  }

  var pi$2 = Math.PI,
      tau$2 = 2 * pi$2,
      epsilon$1 = 1e-6,
      tauEpsilon = tau$2 - epsilon$1;

  function Path() {
    this._x0 = this._y0 = // start of current subpath
    this._x1 = this._y1 = null; // end of current subpath

    this._ = "";
  }

  function path() {
    return new Path();
  }

  Path.prototype = path.prototype = {
    constructor: Path,
    moveTo: function moveTo(x, y) {
      this._ += "M" + (this._x0 = this._x1 = +x) + "," + (this._y0 = this._y1 = +y);
    },
    closePath: function closePath() {
      if (this._x1 !== null) {
        this._x1 = this._x0, this._y1 = this._y0;
        this._ += "Z";
      }
    },
    lineTo: function lineTo(x, y) {
      this._ += "L" + (this._x1 = +x) + "," + (this._y1 = +y);
    },
    quadraticCurveTo: function quadraticCurveTo(x1, y1, x, y) {
      this._ += "Q" + +x1 + "," + +y1 + "," + (this._x1 = +x) + "," + (this._y1 = +y);
    },
    bezierCurveTo: function bezierCurveTo(x1, y1, x2, y2, x, y) {
      this._ += "C" + +x1 + "," + +y1 + "," + +x2 + "," + +y2 + "," + (this._x1 = +x) + "," + (this._y1 = +y);
    },
    arcTo: function arcTo(x1, y1, x2, y2, r) {
      x1 = +x1, y1 = +y1, x2 = +x2, y2 = +y2, r = +r;
      var x0 = this._x1,
          y0 = this._y1,
          x21 = x2 - x1,
          y21 = y2 - y1,
          x01 = x0 - x1,
          y01 = y0 - y1,
          l01_2 = x01 * x01 + y01 * y01; // Is the radius negative? Error.

      if (r < 0) throw new Error("negative radius: " + r); // Is this path empty? Move to (x1,y1).

      if (this._x1 === null) {
        this._ += "M" + (this._x1 = x1) + "," + (this._y1 = y1);
      } // Or, is (x1,y1) coincident with (x0,y0)? Do nothing.
      else if (!(l01_2 > epsilon$1)) ; // Or, are (x0,y0), (x1,y1) and (x2,y2) collinear?
        // Equivalently, is (x1,y1) coincident with (x2,y2)?
        // Or, is the radius zero? Line to (x1,y1).
        else if (!(Math.abs(y01 * x21 - y21 * x01) > epsilon$1) || !r) {
            this._ += "L" + (this._x1 = x1) + "," + (this._y1 = y1);
          } // Otherwise, draw an arc!
          else {
              var x20 = x2 - x0,
                  y20 = y2 - y0,
                  l21_2 = x21 * x21 + y21 * y21,
                  l20_2 = x20 * x20 + y20 * y20,
                  l21 = Math.sqrt(l21_2),
                  l01 = Math.sqrt(l01_2),
                  l = r * Math.tan((pi$2 - Math.acos((l21_2 + l01_2 - l20_2) / (2 * l21 * l01))) / 2),
                  t01 = l / l01,
                  t21 = l / l21; // If the start tangent is not coincident with (x0,y0), line to.

              if (Math.abs(t01 - 1) > epsilon$1) {
                this._ += "L" + (x1 + t01 * x01) + "," + (y1 + t01 * y01);
              }

              this._ += "A" + r + "," + r + ",0,0," + +(y01 * x20 > x01 * y20) + "," + (this._x1 = x1 + t21 * x21) + "," + (this._y1 = y1 + t21 * y21);
            }
    },
    arc: function arc(x, y, r, a0, a1, ccw) {
      x = +x, y = +y, r = +r;
      var dx = r * Math.cos(a0),
          dy = r * Math.sin(a0),
          x0 = x + dx,
          y0 = y + dy,
          cw = 1 ^ ccw,
          da = ccw ? a0 - a1 : a1 - a0; // Is the radius negative? Error.

      if (r < 0) throw new Error("negative radius: " + r); // Is this path empty? Move to (x0,y0).

      if (this._x1 === null) {
        this._ += "M" + x0 + "," + y0;
      } // Or, is (x0,y0) not coincident with the previous point? Line to (x0,y0).
      else if (Math.abs(this._x1 - x0) > epsilon$1 || Math.abs(this._y1 - y0) > epsilon$1) {
          this._ += "L" + x0 + "," + y0;
        } // Is this arc empty? WeвЂ™re done.


      if (!r) return; // Does the angle go the wrong way? Flip the direction.

      if (da < 0) da = da % tau$2 + tau$2; // Is this a complete circle? Draw two arcs to complete the circle.

      if (da > tauEpsilon) {
        this._ += "A" + r + "," + r + ",0,1," + cw + "," + (x - dx) + "," + (y - dy) + "A" + r + "," + r + ",0,1," + cw + "," + (this._x1 = x0) + "," + (this._y1 = y0);
      } // Is this arc non-empty? Draw an arc!
      else if (da > epsilon$1) {
          this._ += "A" + r + "," + r + ",0," + +(da >= pi$2) + "," + cw + "," + (this._x1 = x + r * Math.cos(a1)) + "," + (this._y1 = y + r * Math.sin(a1));
        }
    },
    rect: function rect(x, y, w, h) {
      this._ += "M" + (this._x0 = this._x1 = +x) + "," + (this._y0 = this._y1 = +y) + "h" + +w + "v" + +h + "h" + -w + "Z";
    },
    toString: function toString() {
      return this._;
    }
  };

  function defaultSource(d) {
    return d.source;
  }

  function defaultTarget(d) {
    return d.target;
  }

  function defaultRadius(d) {
    return d.radius;
  }

  function defaultStartAngle(d) {
    return d.startAngle;
  }

  function defaultEndAngle(d) {
    return d.endAngle;
  }

  function ribbon () {
    var source = defaultSource,
        target = defaultTarget,
        radius = defaultRadius,
        startAngle = defaultStartAngle,
        endAngle = defaultEndAngle,
        context = null;

    function ribbon() {
      var buffer,
          argv = slice$2.call(arguments),
          s = source.apply(this, argv),
          t = target.apply(this, argv),
          sr = +radius.apply(this, (argv[0] = s, argv)),
          sa0 = startAngle.apply(this, argv) - halfPi$1,
          sa1 = endAngle.apply(this, argv) - halfPi$1,
          sx0 = sr * cos(sa0),
          sy0 = sr * sin(sa0),
          tr = +radius.apply(this, (argv[0] = t, argv)),
          ta0 = startAngle.apply(this, argv) - halfPi$1,
          ta1 = endAngle.apply(this, argv) - halfPi$1;
      if (!context) context = buffer = path();
      context.moveTo(sx0, sy0);
      context.arc(0, 0, sr, sa0, sa1);

      if (sa0 !== ta0 || sa1 !== ta1) {
        // TODO sr !== tr?
        context.quadraticCurveTo(0, 0, tr * cos(ta0), tr * sin(ta0));
        context.arc(0, 0, tr, ta0, ta1);
      }

      context.quadraticCurveTo(0, 0, sx0, sy0);
      context.closePath();
      if (buffer) return context = null, buffer + "" || null;
    }

    ribbon.radius = function (_) {
      return arguments.length ? (radius = typeof _ === "function" ? _ : constant$5(+_), ribbon) : radius;
    };

    ribbon.startAngle = function (_) {
      return arguments.length ? (startAngle = typeof _ === "function" ? _ : constant$5(+_), ribbon) : startAngle;
    };

    ribbon.endAngle = function (_) {
      return arguments.length ? (endAngle = typeof _ === "function" ? _ : constant$5(+_), ribbon) : endAngle;
    };

    ribbon.source = function (_) {
      return arguments.length ? (source = _, ribbon) : source;
    };

    ribbon.target = function (_) {
      return arguments.length ? (target = _, ribbon) : target;
    };

    ribbon.context = function (_) {
      return arguments.length ? (context = _ == null ? null : _, ribbon) : context;
    };

    return ribbon;
  }

  var prefix = "$";

  function Map() {}

  Map.prototype = map$1.prototype = {
    constructor: Map,
    has: function has(key) {
      return prefix + key in this;
    },
    get: function get(key) {
      return this[prefix + key];
    },
    set: function set(key, value) {
      this[prefix + key] = value;
      return this;
    },
    remove: function remove(key) {
      var property = prefix + key;
      return property in this && delete this[property];
    },
    clear: function clear() {
      for (var property in this) {
        if (property[0] === prefix) delete this[property];
      }
    },
    keys: function keys() {
      var keys = [];

      for (var property in this) {
        if (property[0] === prefix) keys.push(property.slice(1));
      }

      return keys;
    },
    values: function values() {
      var values = [];

      for (var property in this) {
        if (property[0] === prefix) values.push(this[property]);
      }

      return values;
    },
    entries: function entries() {
      var entries = [];

      for (var property in this) {
        if (property[0] === prefix) entries.push({
          key: property.slice(1),
          value: this[property]
        });
      }

      return entries;
    },
    size: function size() {
      var size = 0;

      for (var property in this) {
        if (property[0] === prefix) ++size;
      }

      return size;
    },
    empty: function empty() {
      for (var property in this) {
        if (property[0] === prefix) return false;
      }

      return true;
    },
    each: function each(f) {
      for (var property in this) {
        if (property[0] === prefix) f(this[property], property.slice(1), this);
      }
    }
  };

  function map$1(object, f) {
    var map = new Map(); // Copy constructor.

    if (object instanceof Map) object.each(function (value, key) {
      map.set(key, value);
    }); // Index array by numeric index or specified key function.
    else if (Array.isArray(object)) {
        var i = -1,
            n = object.length,
            o;
        if (f == null) while (++i < n) {
          map.set(i, object[i]);
        } else while (++i < n) {
          map.set(f(o = object[i], i, object), o);
        }
      } // Convert object to map.
      else if (object) for (var key in object) {
          map.set(key, object[key]);
        }
    return map;
  }

  function nest () {
    var keys = [],
        _sortKeys = [],
        _sortValues,
        _rollup,
        nest;

    function apply(array, depth, createResult, setResult) {
      if (depth >= keys.length) {
        if (_sortValues != null) array.sort(_sortValues);
        return _rollup != null ? _rollup(array) : array;
      }

      var i = -1,
          n = array.length,
          key = keys[depth++],
          keyValue,
          value,
          valuesByKey = map$1(),
          values,
          result = createResult();

      while (++i < n) {
        if (values = valuesByKey.get(keyValue = key(value = array[i]) + "")) {
          values.push(value);
        } else {
          valuesByKey.set(keyValue, [value]);
        }
      }

      valuesByKey.each(function (values, key) {
        setResult(result, key, apply(values, depth, createResult, setResult));
      });
      return result;
    }

    function _entries(map, depth) {
      if (++depth > keys.length) return map;
      var array,
          sortKey = _sortKeys[depth - 1];
      if (_rollup != null && depth >= keys.length) array = map.entries();else array = [], map.each(function (v, k) {
        array.push({
          key: k,
          values: _entries(v, depth)
        });
      });
      return sortKey != null ? array.sort(function (a, b) {
        return sortKey(a.key, b.key);
      }) : array;
    }

    return nest = {
      object: function object(array) {
        return apply(array, 0, createObject, setObject);
      },
      map: function map(array) {
        return apply(array, 0, createMap, setMap);
      },
      entries: function entries(array) {
        return _entries(apply(array, 0, createMap, setMap), 0);
      },
      key: function key(d) {
        keys.push(d);
        return nest;
      },
      sortKeys: function sortKeys(order) {
        _sortKeys[keys.length - 1] = order;
        return nest;
      },
      sortValues: function sortValues(order) {
        _sortValues = order;
        return nest;
      },
      rollup: function rollup(f) {
        _rollup = f;
        return nest;
      }
    };
  }

  function createObject() {
    return {};
  }

  function setObject(object, key, value) {
    object[key] = value;
  }

  function createMap() {
    return map$1();
  }

  function setMap(map, key, value) {
    map.set(key, value);
  }

  function Set() {}

  var proto = map$1.prototype;
  Set.prototype = set$2.prototype = {
    constructor: Set,
    has: proto.has,
    add: function add(value) {
      value += "";
      this[prefix + value] = value;
      return this;
    },
    remove: proto.remove,
    clear: proto.clear,
    values: proto.keys,
    size: proto.size,
    empty: proto.empty,
    each: proto.each
  };

  function set$2(object, f) {
    var set = new Set(); // Copy constructor.

    if (object instanceof Set) object.each(function (value) {
      set.add(value);
    }); // Otherwise, assume itвЂ™s an array.
    else if (object) {
        var i = -1,
            n = object.length;
        if (f == null) while (++i < n) {
          set.add(object[i]);
        } else while (++i < n) {
          set.add(f(object[i], i, object));
        }
      }
    return set;
  }

  function keys (map) {
    var keys = [];

    for (var key in map) {
      keys.push(key);
    }

    return keys;
  }

  function values (map) {
    var values = [];

    for (var key in map) {
      values.push(map[key]);
    }

    return values;
  }

  function entries (map) {
    var entries = [];

    for (var key in map) {
      entries.push({
        key: key,
        value: map[key]
      });
    }

    return entries;
  }

  var array$2 = Array.prototype;
  var slice$3 = array$2.slice;

  function ascending$2 (a, b) {
    return a - b;
  }

  function area (ring) {
    var i = 0,
        n = ring.length,
        area = ring[n - 1][1] * ring[0][0] - ring[n - 1][0] * ring[0][1];

    while (++i < n) {
      area += ring[i - 1][1] * ring[i][0] - ring[i - 1][0] * ring[i][1];
    }

    return area;
  }

  function constant$6 (x) {
    return function () {
      return x;
    };
  }

  function contains (ring, hole) {
    var i = -1,
        n = hole.length,
        c;

    while (++i < n) {
      if (c = ringContains(ring, hole[i])) return c;
    }

    return 0;
  }

  function ringContains(ring, point) {
    var x = point[0],
        y = point[1],
        contains = -1;

    for (var i = 0, n = ring.length, j = n - 1; i < n; j = i++) {
      var pi = ring[i],
          xi = pi[0],
          yi = pi[1],
          pj = ring[j],
          xj = pj[0],
          yj = pj[1];
      if (segmentContains(pi, pj, point)) return 0;
      if (yi > y !== yj > y && x < (xj - xi) * (y - yi) / (yj - yi) + xi) contains = -contains;
    }

    return contains;
  }

  function segmentContains(a, b, c) {
    var i;
    return collinear(a, b, c) && within(a[i = +(a[0] === b[0])], c[i], b[i]);
  }

  function collinear(a, b, c) {
    return (b[0] - a[0]) * (c[1] - a[1]) === (c[0] - a[0]) * (b[1] - a[1]);
  }

  function within(p, q, r) {
    return p <= q && q <= r || r <= q && q <= p;
  }

  function noop$1 () {}

  var cases = [[], [[[1.0, 1.5], [0.5, 1.0]]], [[[1.5, 1.0], [1.0, 1.5]]], [[[1.5, 1.0], [0.5, 1.0]]], [[[1.0, 0.5], [1.5, 1.0]]], [[[1.0, 1.5], [0.5, 1.0]], [[1.0, 0.5], [1.5, 1.0]]], [[[1.0, 0.5], [1.0, 1.5]]], [[[1.0, 0.5], [0.5, 1.0]]], [[[0.5, 1.0], [1.0, 0.5]]], [[[1.0, 1.5], [1.0, 0.5]]], [[[0.5, 1.0], [1.0, 0.5]], [[1.5, 1.0], [1.0, 1.5]]], [[[1.5, 1.0], [1.0, 0.5]]], [[[0.5, 1.0], [1.5, 1.0]]], [[[1.0, 1.5], [1.5, 1.0]]], [[[0.5, 1.0], [1.0, 1.5]]], []];
  function contours () {
    var dx = 1,
        dy = 1,
        threshold$$1 = thresholdSturges,
        smooth = smoothLinear;

    function contours(values) {
      var tz = threshold$$1(values); // Convert number of thresholds into uniform thresholds.

      if (!Array.isArray(tz)) {
        var domain = extent(values),
            start = domain[0],
            stop = domain[1];
        tz = tickStep(start, stop, tz);
        tz = sequence(Math.floor(start / tz) * tz, Math.floor(stop / tz) * tz, tz);
      } else {
        tz = tz.slice().sort(ascending$2);
      }

      return tz.map(function (value) {
        return contour(values, value);
      });
    } // Accumulate, smooth contour rings, assign holes to exterior rings.
    // Based on https://github.com/mbostock/shapefile/blob/v0.6.2/shp/polygon.js


    function contour(values, value) {
      var polygons = [],
          holes = [];
      isorings(values, value, function (ring) {
        smooth(ring, values, value);
        if (area(ring) > 0) polygons.push([ring]);else holes.push(ring);
      });
      holes.forEach(function (hole) {
        for (var i = 0, n = polygons.length, polygon; i < n; ++i) {
          if (contains((polygon = polygons[i])[0], hole) !== -1) {
            polygon.push(hole);
            return;
          }
        }
      });
      return {
        type: "MultiPolygon",
        value: value,
        coordinates: polygons
      };
    } // Marching squares with isolines stitched into rings.
    // Based on https://github.com/topojson/topojson-client/blob/v3.0.0/src/stitch.js


    function isorings(values, value, callback) {
      var fragmentByStart = new Array(),
          fragmentByEnd = new Array(),
          x,
          y,
          t0,
          t1,
          t2,
          t3; // Special case for the first row (y = -1, t2 = t3 = 0).

      x = y = -1;
      t1 = values[0] >= value;
      cases[t1 << 1].forEach(stitch);

      while (++x < dx - 1) {
        t0 = t1, t1 = values[x + 1] >= value;
        cases[t0 | t1 << 1].forEach(stitch);
      }

      cases[t1 << 0].forEach(stitch); // General case for the intermediate rows.

      while (++y < dy - 1) {
        x = -1;
        t1 = values[y * dx + dx] >= value;
        t2 = values[y * dx] >= value;
        cases[t1 << 1 | t2 << 2].forEach(stitch);

        while (++x < dx - 1) {
          t0 = t1, t1 = values[y * dx + dx + x + 1] >= value;
          t3 = t2, t2 = values[y * dx + x + 1] >= value;
          cases[t0 | t1 << 1 | t2 << 2 | t3 << 3].forEach(stitch);
        }

        cases[t1 | t2 << 3].forEach(stitch);
      } // Special case for the last row (y = dy - 1, t0 = t1 = 0).


      x = -1;
      t2 = values[y * dx] >= value;
      cases[t2 << 2].forEach(stitch);

      while (++x < dx - 1) {
        t3 = t2, t2 = values[y * dx + x + 1] >= value;
        cases[t2 << 2 | t3 << 3].forEach(stitch);
      }

      cases[t2 << 3].forEach(stitch);

      function stitch(line) {
        var start = [line[0][0] + x, line[0][1] + y],
            end = [line[1][0] + x, line[1][1] + y],
            startIndex = index(start),
            endIndex = index(end),
            f,
            g;

        if (f = fragmentByEnd[startIndex]) {
          if (g = fragmentByStart[endIndex]) {
            delete fragmentByEnd[f.end];
            delete fragmentByStart[g.start];

            if (f === g) {
              f.ring.push(end);
              callback(f.ring);
            } else {
              fragmentByStart[f.start] = fragmentByEnd[g.end] = {
                start: f.start,
                end: g.end,
                ring: f.ring.concat(g.ring)
              };
            }
          } else {
            delete fragmentByEnd[f.end];
            f.ring.push(end);
            fragmentByEnd[f.end = endIndex] = f;
          }
        } else if (f = fragmentByStart[endIndex]) {
          if (g = fragmentByEnd[startIndex]) {
            delete fragmentByStart[f.start];
            delete fragmentByEnd[g.end];

            if (f === g) {
              f.ring.push(end);
              callback(f.ring);
            } else {
              fragmentByStart[g.start] = fragmentByEnd[f.end] = {
                start: g.start,
                end: f.end,
                ring: g.ring.concat(f.ring)
              };
            }
          } else {
            delete fragmentByStart[f.start];
            f.ring.unshift(start);
            fragmentByStart[f.start = startIndex] = f;
          }
        } else {
          fragmentByStart[startIndex] = fragmentByEnd[endIndex] = {
            start: startIndex,
            end: endIndex,
            ring: [start, end]
          };
        }
      }
    }

    function index(point) {
      return point[0] * 2 + point[1] * (dx + 1) * 4;
    }

    function smoothLinear(ring, values, value) {
      ring.forEach(function (point) {
        var x = point[0],
            y = point[1],
            xt = x | 0,
            yt = y | 0,
            v0,
            v1 = values[yt * dx + xt];

        if (x > 0 && x < dx && xt === x) {
          v0 = values[yt * dx + xt - 1];
          point[0] = x + (value - v0) / (v1 - v0) - 0.5;
        }

        if (y > 0 && y < dy && yt === y) {
          v0 = values[(yt - 1) * dx + xt];
          point[1] = y + (value - v0) / (v1 - v0) - 0.5;
        }
      });
    }

    contours.contour = contour;

    contours.size = function (_) {
      if (!arguments.length) return [dx, dy];

      var _0 = Math.ceil(_[0]),
          _1 = Math.ceil(_[1]);

      if (!(_0 > 0) || !(_1 > 0)) throw new Error("invalid size");
      return dx = _0, dy = _1, contours;
    };

    contours.thresholds = function (_) {
      return arguments.length ? (threshold$$1 = typeof _ === "function" ? _ : Array.isArray(_) ? constant$6(slice$3.call(_)) : constant$6(_), contours) : threshold$$1;
    };

    contours.smooth = function (_) {
      return arguments.length ? (smooth = _ ? smoothLinear : noop$1, contours) : smooth === smoothLinear;
    };

    return contours;
  }

  // TODO Optimize edge cases.
  // TODO Optimize index calculation.
  // TODO Optimize arguments.
  function blurX(source, target, r) {
    var n = source.width,
        m = source.height,
        w = (r << 1) + 1;

    for (var j = 0; j < m; ++j) {
      for (var i = 0, sr = 0; i < n + r; ++i) {
        if (i < n) {
          sr += source.data[i + j * n];
        }

        if (i >= r) {
          if (i >= w) {
            sr -= source.data[i - w + j * n];
          }

          target.data[i - r + j * n] = sr / Math.min(i + 1, n - 1 + w - i, w);
        }
      }
    }
  } // TODO Optimize edge cases.
  // TODO Optimize index calculation.
  // TODO Optimize arguments.

  function blurY(source, target, r) {
    var n = source.width,
        m = source.height,
        w = (r << 1) + 1;

    for (var i = 0; i < n; ++i) {
      for (var j = 0, sr = 0; j < m + r; ++j) {
        if (j < m) {
          sr += source.data[i + j * n];
        }

        if (j >= r) {
          if (j >= w) {
            sr -= source.data[i + (j - w) * n];
          }

          target.data[i + (j - r) * n] = sr / Math.min(j + 1, m - 1 + w - j, w);
        }
      }
    }
  }

  function defaultX(d) {
    return d[0];
  }

  function defaultY(d) {
    return d[1];
  }

  function defaultWeight() {
    return 1;
  }

  function density () {
    var x = defaultX,
        y = defaultY,
        weight = defaultWeight,
        dx = 960,
        dy = 500,
        r = 20,
        // blur radius
    k = 2,
        // log2(grid cell size)
    o = r * 3,
        // grid offset, to pad for blur
    n = dx + o * 2 >> k,
        // grid width
    m = dy + o * 2 >> k,
        // grid height
    threshold$$1 = constant$6(20);

    function density(data) {
      var values0 = new Float32Array(n * m),
          values1 = new Float32Array(n * m);
      data.forEach(function (d, i, data) {
        var xi = +x(d, i, data) + o >> k,
            yi = +y(d, i, data) + o >> k,
            wi = +weight(d, i, data);

        if (xi >= 0 && xi < n && yi >= 0 && yi < m) {
          values0[xi + yi * n] += wi;
        }
      }); // TODO Optimize.

      blurX({
        width: n,
        height: m,
        data: values0
      }, {
        width: n,
        height: m,
        data: values1
      }, r >> k);
      blurY({
        width: n,
        height: m,
        data: values1
      }, {
        width: n,
        height: m,
        data: values0
      }, r >> k);
      blurX({
        width: n,
        height: m,
        data: values0
      }, {
        width: n,
        height: m,
        data: values1
      }, r >> k);
      blurY({
        width: n,
        height: m,
        data: values1
      }, {
        width: n,
        height: m,
        data: values0
      }, r >> k);
      blurX({
        width: n,
        height: m,
        data: values0
      }, {
        width: n,
        height: m,
        data: values1
      }, r >> k);
      blurY({
        width: n,
        height: m,
        data: values1
      }, {
        width: n,
        height: m,
        data: values0
      }, r >> k);
      var tz = threshold$$1(values0); // Convert number of thresholds into uniform thresholds.

      if (!Array.isArray(tz)) {
        var stop = max(values0);
        tz = tickStep(0, stop, tz);
        tz = sequence(0, Math.floor(stop / tz) * tz, tz);
        tz.shift();
      }

      return contours().thresholds(tz).size([n, m])(values0).map(transform);
    }

    function transform(geometry) {
      geometry.value *= Math.pow(2, -2 * k); // Density in points per square pixel.

      geometry.coordinates.forEach(transformPolygon);
      return geometry;
    }

    function transformPolygon(coordinates) {
      coordinates.forEach(transformRing);
    }

    function transformRing(coordinates) {
      coordinates.forEach(transformPoint);
    } // TODO Optimize.


    function transformPoint(coordinates) {
      coordinates[0] = coordinates[0] * Math.pow(2, k) - o;
      coordinates[1] = coordinates[1] * Math.pow(2, k) - o;
    }

    function resize() {
      o = r * 3;
      n = dx + o * 2 >> k;
      m = dy + o * 2 >> k;
      return density;
    }

    density.x = function (_) {
      return arguments.length ? (x = typeof _ === "function" ? _ : constant$6(+_), density) : x;
    };

    density.y = function (_) {
      return arguments.length ? (y = typeof _ === "function" ? _ : constant$6(+_), density) : y;
    };

    density.weight = function (_) {
      return arguments.length ? (weight = typeof _ === "function" ? _ : constant$6(+_), density) : weight;
    };

    density.size = function (_) {
      if (!arguments.length) return [dx, dy];

      var _0 = Math.ceil(_[0]),
          _1 = Math.ceil(_[1]);

      if (!(_0 >= 0) && !(_0 >= 0)) throw new Error("invalid size");
      return dx = _0, dy = _1, resize();
    };

    density.cellSize = function (_) {
      if (!arguments.length) return 1 << k;
      if (!((_ = +_) >= 1)) throw new Error("invalid cell size");
      return k = Math.floor(Math.log(_) / Math.LN2), resize();
    };

    density.thresholds = function (_) {
      return arguments.length ? (threshold$$1 = typeof _ === "function" ? _ : Array.isArray(_) ? constant$6(slice$3.call(_)) : constant$6(_), density) : threshold$$1;
    };

    density.bandwidth = function (_) {
      if (!arguments.length) return Math.sqrt(r * (r + 1));
      if (!((_ = +_) >= 0)) throw new Error("invalid bandwidth");
      return r = Math.round((Math.sqrt(4 * _ * _ + 1) - 1) / 2), resize();
    };

    return density;
  }

  var EOL = {},
      EOF = {},
      QUOTE = 34,
      NEWLINE = 10,
      RETURN = 13;

  function objectConverter(columns) {
    return new Function("d", "return {" + columns.map(function (name, i) {
      return JSON.stringify(name) + ": d[" + i + "]";
    }).join(",") + "}");
  }

  function customConverter(columns, f) {
    var object = objectConverter(columns);
    return function (row, i) {
      return f(object(row), i, columns);
    };
  } // Compute unique columns in order of discovery.


  function inferColumns(rows) {
    var columnSet = Object.create(null),
        columns = [];
    rows.forEach(function (row) {
      for (var column in row) {
        if (!(column in columnSet)) {
          columns.push(columnSet[column] = column);
        }
      }
    });
    return columns;
  }

  function pad(value, width) {
    var s = value + "",
        length = s.length;
    return length < width ? new Array(width - length + 1).join(0) + s : s;
  }

  function formatYear(year) {
    return year < 0 ? "-" + pad(-year, 6) : year > 9999 ? "+" + pad(year, 6) : pad(year, 4);
  }

  function formatDate(date) {
    var hours = date.getUTCHours(),
        minutes = date.getUTCMinutes(),
        seconds = date.getUTCSeconds(),
        milliseconds = date.getUTCMilliseconds();
    return isNaN(date) ? "Invalid Date" : formatYear(date.getUTCFullYear(), 4) + "-" + pad(date.getUTCMonth() + 1, 2) + "-" + pad(date.getUTCDate(), 2) + (milliseconds ? "T" + pad(hours, 2) + ":" + pad(minutes, 2) + ":" + pad(seconds, 2) + "." + pad(milliseconds, 3) + "Z" : seconds ? "T" + pad(hours, 2) + ":" + pad(minutes, 2) + ":" + pad(seconds, 2) + "Z" : minutes || hours ? "T" + pad(hours, 2) + ":" + pad(minutes, 2) + "Z" : "");
  }

  function dsvFormat (delimiter) {
    var reFormat = new RegExp("[\"" + delimiter + "\n\r]"),
        DELIMITER = delimiter.charCodeAt(0);

    function parse(text, f) {
      var convert,
          columns,
          rows = parseRows(text, function (row, i) {
        if (convert) return convert(row, i - 1);
        columns = row, convert = f ? customConverter(row, f) : objectConverter(row);
      });
      rows.columns = columns || [];
      return rows;
    }

    function parseRows(text, f) {
      var rows = [],
          // output rows
      N = text.length,
          I = 0,
          // current character index
      n = 0,
          // current line number
      t,
          // current token
      eof = N <= 0,
          // current token followed by EOF?
      eol = false; // current token followed by EOL?
      // Strip the trailing newline.

      if (text.charCodeAt(N - 1) === NEWLINE) --N;
      if (text.charCodeAt(N - 1) === RETURN) --N;

      function token() {
        if (eof) return EOF;
        if (eol) return eol = false, EOL; // Unescape quotes.

        var i,
            j = I,
            c;

        if (text.charCodeAt(j) === QUOTE) {
          while (I++ < N && text.charCodeAt(I) !== QUOTE || text.charCodeAt(++I) === QUOTE) {
          }

          if ((i = I) >= N) eof = true;else if ((c = text.charCodeAt(I++)) === NEWLINE) eol = true;else if (c === RETURN) {
            eol = true;
            if (text.charCodeAt(I) === NEWLINE) ++I;
          }
          return text.slice(j + 1, i - 1).replace(/""/g, "\"");
        } // Find next delimiter or newline.


        while (I < N) {
          if ((c = text.charCodeAt(i = I++)) === NEWLINE) eol = true;else if (c === RETURN) {
            eol = true;
            if (text.charCodeAt(I) === NEWLINE) ++I;
          } else if (c !== DELIMITER) continue;
          return text.slice(j, i);
        } // Return last token before EOF.


        return eof = true, text.slice(j, N);
      }

      while ((t = token()) !== EOF) {
        var row = [];

        while (t !== EOL && t !== EOF) {
          row.push(t), t = token();
        }

        if (f && (row = f(row, n++)) == null) continue;
        rows.push(row);
      }

      return rows;
    }

    function preformatBody(rows, columns) {
      return rows.map(function (row) {
        return columns.map(function (column) {
          return formatValue(row[column]);
        }).join(delimiter);
      });
    }

    function format(rows, columns) {
      if (columns == null) columns = inferColumns(rows);
      return [columns.map(formatValue).join(delimiter)].concat(preformatBody(rows, columns)).join("\n");
    }

    function formatBody(rows, columns) {
      if (columns == null) columns = inferColumns(rows);
      return preformatBody(rows, columns).join("\n");
    }

    function formatRows(rows) {
      return rows.map(formatRow).join("\n");
    }

    function formatRow(row) {
      return row.map(formatValue).join(delimiter);
    }

    function formatValue(value) {
      return value == null ? "" : value instanceof Date ? formatDate(value) : reFormat.test(value += "") ? "\"" + value.replace(/"/g, "\"\"") + "\"" : value;
    }

    return {
      parse: parse,
      parseRows: parseRows,
      format: format,
      formatBody: formatBody,
      formatRows: formatRows
    };
  }

  var csv = dsvFormat(",");
  var csvParse = csv.parse;
  var csvParseRows = csv.parseRows;
  var csvFormat = csv.format;
  var csvFormatBody = csv.formatBody;
  var csvFormatRows = csv.formatRows;

  var tsv = dsvFormat("\t");
  var tsvParse = tsv.parse;
  var tsvParseRows = tsv.parseRows;
  var tsvFormat = tsv.format;
  var tsvFormatBody = tsv.formatBody;
  var tsvFormatRows = tsv.formatRows;

  function autoType(object) {
    for (var key in object) {
      var value = object[key].trim(),
          number;
      if (!value) value = null;else if (value === "true") value = true;else if (value === "false") value = false;else if (value === "NaN") value = NaN;else if (!isNaN(number = +value)) value = number;else if (/^([-+]\d{2})?\d{4}(-\d{2}(-\d{2})?)?(T\d{2}:\d{2}(:\d{2}(\.\d{3})?)?(Z|[-+]\d{2}:\d{2})?)?$/.test(value)) value = new Date(value);else continue;
      object[key] = value;
    }

    return object;
  }

  function responseBlob(response) {
    if (!response.ok) throw new Error(response.status + " " + response.statusText);
    return response.blob();
  }

  function blob (input, init) {
    return fetch(input, init).then(responseBlob);
  }

  function responseArrayBuffer(response) {
    if (!response.ok) throw new Error(response.status + " " + response.statusText);
    return response.arrayBuffer();
  }

  function buffer (input, init) {
    return fetch(input, init).then(responseArrayBuffer);
  }

  function responseText(response) {
    if (!response.ok) throw new Error(response.status + " " + response.statusText);
    return response.text();
  }

  function text (input, init) {
    return fetch(input, init).then(responseText);
  }

  function dsvParse(parse) {
    return function (input, init, row) {
      if (arguments.length === 2 && typeof init === "function") row = init, init = undefined;
      return text(input, init).then(function (response) {
        return parse(response, row);
      });
    };
  }

  function dsv(delimiter, input, init, row) {
    if (arguments.length === 3 && typeof init === "function") row = init, init = undefined;
    var format = dsvFormat(delimiter);
    return text(input, init).then(function (response) {
      return format.parse(response, row);
    });
  }
  var csv$1 = dsvParse(csvParse);
  var tsv$1 = dsvParse(tsvParse);

  function image (input, init) {
    return new Promise(function (resolve, reject) {
      var image = new Image();

      for (var key in init) {
        image[key] = init[key];
      }

      image.onerror = reject;

      image.onload = function () {
        resolve(image);
      };

      image.src = input;
    });
  }

  function responseJson(response) {
    if (!response.ok) throw new Error(response.status + " " + response.statusText);
    return response.json();
  }

  function json (input, init) {
    return fetch(input, init).then(responseJson);
  }

  function parser(type) {
    return function (input, init) {
      return text(input, init).then(function (text$$1) {
        return new DOMParser().parseFromString(text$$1, type);
      });
    };
  }

  var xml = parser("application/xml");
  var html = parser("text/html");
  var svg = parser("image/svg+xml");

  function center$1 (x, y) {
    var nodes;
    if (x == null) x = 0;
    if (y == null) y = 0;

    function force() {
      var i,
          n = nodes.length,
          node,
          sx = 0,
          sy = 0;

      for (i = 0; i < n; ++i) {
        node = nodes[i], sx += node.x, sy += node.y;
      }

      for (sx = sx / n - x, sy = sy / n - y, i = 0; i < n; ++i) {
        node = nodes[i], node.x -= sx, node.y -= sy;
      }
    }

    force.initialize = function (_) {
      nodes = _;
    };

    force.x = function (_) {
      return arguments.length ? (x = +_, force) : x;
    };

    force.y = function (_) {
      return arguments.length ? (y = +_, force) : y;
    };

    return force;
  }

  function constant$7 (x) {
    return function () {
      return x;
    };
  }

  function jiggle () {
    return (Math.random() - 0.5) * 1e-6;
  }

  function tree_add (d) {
    var x = +this._x.call(null, d),
        y = +this._y.call(null, d);
    return add(this.cover(x, y), x, y, d);
  }

  function add(tree, x, y, d) {
    if (isNaN(x) || isNaN(y)) return tree; // ignore invalid points

    var parent,
        node = tree._root,
        leaf = {
      data: d
    },
        x0 = tree._x0,
        y0 = tree._y0,
        x1 = tree._x1,
        y1 = tree._y1,
        xm,
        ym,
        xp,
        yp,
        right,
        bottom,
        i,
        j; // If the tree is empty, initialize the root as a leaf.

    if (!node) return tree._root = leaf, tree; // Find the existing leaf for the new point, or add it.

    while (node.length) {
      if (right = x >= (xm = (x0 + x1) / 2)) x0 = xm;else x1 = xm;
      if (bottom = y >= (ym = (y0 + y1) / 2)) y0 = ym;else y1 = ym;
      if (parent = node, !(node = node[i = bottom << 1 | right])) return parent[i] = leaf, tree;
    } // Is the new point is exactly coincident with the existing point?


    xp = +tree._x.call(null, node.data);
    yp = +tree._y.call(null, node.data);
    if (x === xp && y === yp) return leaf.next = node, parent ? parent[i] = leaf : tree._root = leaf, tree; // Otherwise, split the leaf node until the old and new point are separated.

    do {
      parent = parent ? parent[i] = new Array(4) : tree._root = new Array(4);
      if (right = x >= (xm = (x0 + x1) / 2)) x0 = xm;else x1 = xm;
      if (bottom = y >= (ym = (y0 + y1) / 2)) y0 = ym;else y1 = ym;
    } while ((i = bottom << 1 | right) === (j = (yp >= ym) << 1 | xp >= xm));

    return parent[j] = node, parent[i] = leaf, tree;
  }

  function addAll(data) {
    var d,
        i,
        n = data.length,
        x,
        y,
        xz = new Array(n),
        yz = new Array(n),
        x0 = Infinity,
        y0 = Infinity,
        x1 = -Infinity,
        y1 = -Infinity; // Compute the points and their extent.

    for (i = 0; i < n; ++i) {
      if (isNaN(x = +this._x.call(null, d = data[i])) || isNaN(y = +this._y.call(null, d))) continue;
      xz[i] = x;
      yz[i] = y;
      if (x < x0) x0 = x;
      if (x > x1) x1 = x;
      if (y < y0) y0 = y;
      if (y > y1) y1 = y;
    } // If there were no (valid) points, abort.


    if (x0 > x1 || y0 > y1) return this; // Expand the tree to cover the new points.

    this.cover(x0, y0).cover(x1, y1); // Add the new points.

    for (i = 0; i < n; ++i) {
      add(this, xz[i], yz[i], data[i]);
    }

    return this;
  }

  function tree_cover (x, y) {
    if (isNaN(x = +x) || isNaN(y = +y)) return this; // ignore invalid points

    var x0 = this._x0,
        y0 = this._y0,
        x1 = this._x1,
        y1 = this._y1; // If the quadtree has no extent, initialize them.
    // Integer extent are necessary so that if we later double the extent,
    // the existing quadrant boundaries donвЂ™t change due to floating point error!

    if (isNaN(x0)) {
      x1 = (x0 = Math.floor(x)) + 1;
      y1 = (y0 = Math.floor(y)) + 1;
    } // Otherwise, double repeatedly to cover.
    else {
        var z = x1 - x0,
            node = this._root,
            parent,
            i;

        while (x0 > x || x >= x1 || y0 > y || y >= y1) {
          i = (y < y0) << 1 | x < x0;
          parent = new Array(4), parent[i] = node, node = parent, z *= 2;

          switch (i) {
            case 0:
              x1 = x0 + z, y1 = y0 + z;
              break;

            case 1:
              x0 = x1 - z, y1 = y0 + z;
              break;

            case 2:
              x1 = x0 + z, y0 = y1 - z;
              break;

            case 3:
              x0 = x1 - z, y0 = y1 - z;
              break;
          }
        }

        if (this._root && this._root.length) this._root = node;
      }

    this._x0 = x0;
    this._y0 = y0;
    this._x1 = x1;
    this._y1 = y1;
    return this;
  }

  function tree_data () {
    var data = [];
    this.visit(function (node) {
      if (!node.length) do {
        data.push(node.data);
      } while (node = node.next);
    });
    return data;
  }

  function tree_extent (_) {
    return arguments.length ? this.cover(+_[0][0], +_[0][1]).cover(+_[1][0], +_[1][1]) : isNaN(this._x0) ? undefined : [[this._x0, this._y0], [this._x1, this._y1]];
  }

  function Quad (node, x0, y0, x1, y1) {
    this.node = node;
    this.x0 = x0;
    this.y0 = y0;
    this.x1 = x1;
    this.y1 = y1;
  }

  function tree_find (x, y, radius) {
    var data,
        x0 = this._x0,
        y0 = this._y0,
        x1,
        y1,
        x2,
        y2,
        x3 = this._x1,
        y3 = this._y1,
        quads = [],
        node = this._root,
        q,
        i;
    if (node) quads.push(new Quad(node, x0, y0, x3, y3));
    if (radius == null) radius = Infinity;else {
      x0 = x - radius, y0 = y - radius;
      x3 = x + radius, y3 = y + radius;
      radius *= radius;
    }

    while (q = quads.pop()) {
      // Stop searching if this quadrant canвЂ™t contain a closer node.
      if (!(node = q.node) || (x1 = q.x0) > x3 || (y1 = q.y0) > y3 || (x2 = q.x1) < x0 || (y2 = q.y1) < y0) continue; // Bisect the current quadrant.

      if (node.length) {
        var xm = (x1 + x2) / 2,
            ym = (y1 + y2) / 2;
        quads.push(new Quad(node[3], xm, ym, x2, y2), new Quad(node[2], x1, ym, xm, y2), new Quad(node[1], xm, y1, x2, ym), new Quad(node[0], x1, y1, xm, ym)); // Visit the closest quadrant first.

        if (i = (y >= ym) << 1 | x >= xm) {
          q = quads[quads.length - 1];
          quads[quads.length - 1] = quads[quads.length - 1 - i];
          quads[quads.length - 1 - i] = q;
        }
      } // Visit this point. (Visiting coincident points isnвЂ™t necessary!)
      else {
          var dx = x - +this._x.call(null, node.data),
              dy = y - +this._y.call(null, node.data),
              d2 = dx * dx + dy * dy;

          if (d2 < radius) {
            var d = Math.sqrt(radius = d2);
            x0 = x - d, y0 = y - d;
            x3 = x + d, y3 = y + d;
            data = node.data;
          }
        }
    }

    return data;
  }

  function tree_remove (d) {
    if (isNaN(x = +this._x.call(null, d)) || isNaN(y = +this._y.call(null, d))) return this; // ignore invalid points

    var parent,
        node = this._root,
        retainer,
        previous,
        next,
        x0 = this._x0,
        y0 = this._y0,
        x1 = this._x1,
        y1 = this._y1,
        x,
        y,
        xm,
        ym,
        right,
        bottom,
        i,
        j; // If the tree is empty, initialize the root as a leaf.

    if (!node) return this; // Find the leaf node for the point.
    // While descending, also retain the deepest parent with a non-removed sibling.

    if (node.length) while (true) {
      if (right = x >= (xm = (x0 + x1) / 2)) x0 = xm;else x1 = xm;
      if (bottom = y >= (ym = (y0 + y1) / 2)) y0 = ym;else y1 = ym;
      if (!(parent = node, node = node[i = bottom << 1 | right])) return this;
      if (!node.length) break;
      if (parent[i + 1 & 3] || parent[i + 2 & 3] || parent[i + 3 & 3]) retainer = parent, j = i;
    } // Find the point to remove.

    while (node.data !== d) {
      if (!(previous = node, node = node.next)) return this;
    }

    if (next = node.next) delete node.next; // If there are multiple coincident points, remove just the point.

    if (previous) return next ? previous.next = next : delete previous.next, this; // If this is the root point, remove it.

    if (!parent) return this._root = next, this; // Remove this leaf.

    next ? parent[i] = next : delete parent[i]; // If the parent now contains exactly one leaf, collapse superfluous parents.

    if ((node = parent[0] || parent[1] || parent[2] || parent[3]) && node === (parent[3] || parent[2] || parent[1] || parent[0]) && !node.length) {
      if (retainer) retainer[j] = node;else this._root = node;
    }

    return this;
  }
  function removeAll(data) {
    for (var i = 0, n = data.length; i < n; ++i) {
      this.remove(data[i]);
    }

    return this;
  }

  function tree_root () {
    return this._root;
  }

  function tree_size () {
    var size = 0;
    this.visit(function (node) {
      if (!node.length) do {
        ++size;
      } while (node = node.next);
    });
    return size;
  }

  function tree_visit (callback) {
    var quads = [],
        q,
        node = this._root,
        child,
        x0,
        y0,
        x1,
        y1;
    if (node) quads.push(new Quad(node, this._x0, this._y0, this._x1, this._y1));

    while (q = quads.pop()) {
      if (!callback(node = q.node, x0 = q.x0, y0 = q.y0, x1 = q.x1, y1 = q.y1) && node.length) {
        var xm = (x0 + x1) / 2,
            ym = (y0 + y1) / 2;
        if (child = node[3]) quads.push(new Quad(child, xm, ym, x1, y1));
        if (child = node[2]) quads.push(new Quad(child, x0, ym, xm, y1));
        if (child = node[1]) quads.push(new Quad(child, xm, y0, x1, ym));
        if (child = node[0]) quads.push(new Quad(child, x0, y0, xm, ym));
      }
    }

    return this;
  }

  function tree_visitAfter (callback) {
    var quads = [],
        next = [],
        q;
    if (this._root) quads.push(new Quad(this._root, this._x0, this._y0, this._x1, this._y1));

    while (q = quads.pop()) {
      var node = q.node;

      if (node.length) {
        var child,
            x0 = q.x0,
            y0 = q.y0,
            x1 = q.x1,
            y1 = q.y1,
            xm = (x0 + x1) / 2,
            ym = (y0 + y1) / 2;
        if (child = node[0]) quads.push(new Quad(child, x0, y0, xm, ym));
        if (child = node[1]) quads.push(new Quad(child, xm, y0, x1, ym));
        if (child = node[2]) quads.push(new Quad(child, x0, ym, xm, y1));
        if (child = node[3]) quads.push(new Quad(child, xm, ym, x1, y1));
      }

      next.push(q);
    }

    while (q = next.pop()) {
      callback(q.node, q.x0, q.y0, q.x1, q.y1);
    }

    return this;
  }

  function defaultX$1(d) {
    return d[0];
  }
  function tree_x (_) {
    return arguments.length ? (this._x = _, this) : this._x;
  }

  function defaultY$1(d) {
    return d[1];
  }
  function tree_y (_) {
    return arguments.length ? (this._y = _, this) : this._y;
  }

  function quadtree(nodes, x, y) {
    var tree = new Quadtree(x == null ? defaultX$1 : x, y == null ? defaultY$1 : y, NaN, NaN, NaN, NaN);
    return nodes == null ? tree : tree.addAll(nodes);
  }

  function Quadtree(x, y, x0, y0, x1, y1) {
    this._x = x;
    this._y = y;
    this._x0 = x0;
    this._y0 = y0;
    this._x1 = x1;
    this._y1 = y1;
    this._root = undefined;
  }

  function leaf_copy(leaf) {
    var copy = {
      data: leaf.data
    },
        next = copy;

    while (leaf = leaf.next) {
      next = next.next = {
        data: leaf.data
      };
    }

    return copy;
  }

  var treeProto = quadtree.prototype = Quadtree.prototype;

  treeProto.copy = function () {
    var copy = new Quadtree(this._x, this._y, this._x0, this._y0, this._x1, this._y1),
        node = this._root,
        nodes,
        child;
    if (!node) return copy;
    if (!node.length) return copy._root = leaf_copy(node), copy;
    nodes = [{
      source: node,
      target: copy._root = new Array(4)
    }];

    while (node = nodes.pop()) {
      for (var i = 0; i < 4; ++i) {
        if (child = node.source[i]) {
          if (child.length) nodes.push({
            source: child,
            target: node.target[i] = new Array(4)
          });else node.target[i] = leaf_copy(child);
        }
      }
    }

    return copy;
  };

  treeProto.add = tree_add;
  treeProto.addAll = addAll;
  treeProto.cover = tree_cover;
  treeProto.data = tree_data;
  treeProto.extent = tree_extent;
  treeProto.find = tree_find;
  treeProto.remove = tree_remove;
  treeProto.removeAll = removeAll;
  treeProto.root = tree_root;
  treeProto.size = tree_size;
  treeProto.visit = tree_visit;
  treeProto.visitAfter = tree_visitAfter;
  treeProto.x = tree_x;
  treeProto.y = tree_y;

  function x(d) {
    return d.x + d.vx;
  }

  function y(d) {
    return d.y + d.vy;
  }

  function collide (radius) {
    var nodes,
        radii,
        strength = 1,
        iterations = 1;
    if (typeof radius !== "function") radius = constant$7(radius == null ? 1 : +radius);

    function force() {
      var i,
          n = nodes.length,
          tree,
          node,
          xi,
          yi,
          ri,
          ri2;

      for (var k = 0; k < iterations; ++k) {
        tree = quadtree(nodes, x, y).visitAfter(prepare);

        for (i = 0; i < n; ++i) {
          node = nodes[i];
          ri = radii[node.index], ri2 = ri * ri;
          xi = node.x + node.vx;
          yi = node.y + node.vy;
          tree.visit(apply);
        }
      }

      function apply(quad, x0, y0, x1, y1) {
        var data = quad.data,
            rj = quad.r,
            r = ri + rj;

        if (data) {
          if (data.index > node.index) {
            var x = xi - data.x - data.vx,
                y = yi - data.y - data.vy,
                l = x * x + y * y;

            if (l < r * r) {
              if (x === 0) x = jiggle(), l += x * x;
              if (y === 0) y = jiggle(), l += y * y;
              l = (r - (l = Math.sqrt(l))) / l * strength;
              node.vx += (x *= l) * (r = (rj *= rj) / (ri2 + rj));
              node.vy += (y *= l) * r;
              data.vx -= x * (r = 1 - r);
              data.vy -= y * r;
            }
          }

          return;
        }

        return x0 > xi + r || x1 < xi - r || y0 > yi + r || y1 < yi - r;
      }
    }

    function prepare(quad) {
      if (quad.data) return quad.r = radii[quad.data.index];

      for (var i = quad.r = 0; i < 4; ++i) {
        if (quad[i] && quad[i].r > quad.r) {
          quad.r = quad[i].r;
        }
      }
    }

    function initialize() {
      if (!nodes) return;
      var i,
          n = nodes.length,
          node;
      radii = new Array(n);

      for (i = 0; i < n; ++i) {
        node = nodes[i], radii[node.index] = +radius(node, i, nodes);
      }
    }

    force.initialize = function (_) {
      nodes = _;
      initialize();
    };

    force.iterations = function (_) {
      return arguments.length ? (iterations = +_, force) : iterations;
    };

    force.strength = function (_) {
      return arguments.length ? (strength = +_, force) : strength;
    };

    force.radius = function (_) {
      return arguments.length ? (radius = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : radius;
    };

    return force;
  }

  function index(d) {
    return d.index;
  }

  function find(nodeById, nodeId) {
    var node = nodeById.get(nodeId);
    if (!node) throw new Error("missing: " + nodeId);
    return node;
  }

  function link (links) {
    var id = index,
        strength = defaultStrength,
        strengths,
        distance = constant$7(30),
        distances,
        nodes,
        count,
        bias,
        iterations = 1;
    if (links == null) links = [];

    function defaultStrength(link) {
      return 1 / Math.min(count[link.source.index], count[link.target.index]);
    }

    function force(alpha) {
      for (var k = 0, n = links.length; k < iterations; ++k) {
        for (var i = 0, link, source, target, x, y, l, b; i < n; ++i) {
          link = links[i], source = link.source, target = link.target;
          x = target.x + target.vx - source.x - source.vx || jiggle();
          y = target.y + target.vy - source.y - source.vy || jiggle();
          l = Math.sqrt(x * x + y * y);
          l = (l - distances[i]) / l * alpha * strengths[i];
          x *= l, y *= l;
          target.vx -= x * (b = bias[i]);
          target.vy -= y * b;
          source.vx += x * (b = 1 - b);
          source.vy += y * b;
        }
      }
    }

    function initialize() {
      if (!nodes) return;
      var i,
          n = nodes.length,
          m = links.length,
          nodeById = map$1(nodes, id),
          link;

      for (i = 0, count = new Array(n); i < m; ++i) {
        link = links[i], link.index = i;
        if (babelHelpers.typeof(link.source) !== "object") link.source = find(nodeById, link.source);
        if (babelHelpers.typeof(link.target) !== "object") link.target = find(nodeById, link.target);
        count[link.source.index] = (count[link.source.index] || 0) + 1;
        count[link.target.index] = (count[link.target.index] || 0) + 1;
      }

      for (i = 0, bias = new Array(m); i < m; ++i) {
        link = links[i], bias[i] = count[link.source.index] / (count[link.source.index] + count[link.target.index]);
      }

      strengths = new Array(m), initializeStrength();
      distances = new Array(m), initializeDistance();
    }

    function initializeStrength() {
      if (!nodes) return;

      for (var i = 0, n = links.length; i < n; ++i) {
        strengths[i] = +strength(links[i], i, links);
      }
    }

    function initializeDistance() {
      if (!nodes) return;

      for (var i = 0, n = links.length; i < n; ++i) {
        distances[i] = +distance(links[i], i, links);
      }
    }

    force.initialize = function (_) {
      nodes = _;
      initialize();
    };

    force.links = function (_) {
      return arguments.length ? (links = _, initialize(), force) : links;
    };

    force.id = function (_) {
      return arguments.length ? (id = _, force) : id;
    };

    force.iterations = function (_) {
      return arguments.length ? (iterations = +_, force) : iterations;
    };

    force.strength = function (_) {
      return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initializeStrength(), force) : strength;
    };

    force.distance = function (_) {
      return arguments.length ? (distance = typeof _ === "function" ? _ : constant$7(+_), initializeDistance(), force) : distance;
    };

    return force;
  }

  function x$1(d) {
    return d.x;
  }
  function y$1(d) {
    return d.y;
  }
  var initialRadius = 10,
      initialAngle = Math.PI * (3 - Math.sqrt(5));
  function simulation (_nodes) {
    var simulation,
        _alpha = 1,
        _alphaMin = 0.001,
        _alphaDecay = 1 - Math.pow(_alphaMin, 1 / 300),
        _alphaTarget = 0,
        _velocityDecay = 0.6,
        forces = map$1(),
        stepper = timer(step),
        event = dispatch("tick", "end");

    if (_nodes == null) _nodes = [];

    function step() {
      tick();
      event.call("tick", simulation);

      if (_alpha < _alphaMin) {
        stepper.stop();
        event.call("end", simulation);
      }
    }

    function tick(iterations) {
      var i,
          n = _nodes.length,
          node;
      if (iterations === undefined) iterations = 1;

      for (var k = 0; k < iterations; ++k) {
        _alpha += (_alphaTarget - _alpha) * _alphaDecay;
        forces.each(function (force) {
          force(_alpha);
        });

        for (i = 0; i < n; ++i) {
          node = _nodes[i];
          if (node.fx == null) node.x += node.vx *= _velocityDecay;else node.x = node.fx, node.vx = 0;
          if (node.fy == null) node.y += node.vy *= _velocityDecay;else node.y = node.fy, node.vy = 0;
        }
      }

      return simulation;
    }

    function initializeNodes() {
      for (var i = 0, n = _nodes.length, node; i < n; ++i) {
        node = _nodes[i], node.index = i;
        if (node.fx != null) node.x = node.fx;
        if (node.fy != null) node.y = node.fy;

        if (isNaN(node.x) || isNaN(node.y)) {
          var radius = initialRadius * Math.sqrt(i),
              angle = i * initialAngle;
          node.x = radius * Math.cos(angle);
          node.y = radius * Math.sin(angle);
        }

        if (isNaN(node.vx) || isNaN(node.vy)) {
          node.vx = node.vy = 0;
        }
      }
    }

    function initializeForce(force) {
      if (force.initialize) force.initialize(_nodes);
      return force;
    }

    initializeNodes();
    return simulation = {
      tick: tick,
      restart: function restart() {
        return stepper.restart(step), simulation;
      },
      stop: function stop() {
        return stepper.stop(), simulation;
      },
      nodes: function nodes(_) {
        return arguments.length ? (_nodes = _, initializeNodes(), forces.each(initializeForce), simulation) : _nodes;
      },
      alpha: function alpha(_) {
        return arguments.length ? (_alpha = +_, simulation) : _alpha;
      },
      alphaMin: function alphaMin(_) {
        return arguments.length ? (_alphaMin = +_, simulation) : _alphaMin;
      },
      alphaDecay: function alphaDecay(_) {
        return arguments.length ? (_alphaDecay = +_, simulation) : +_alphaDecay;
      },
      alphaTarget: function alphaTarget(_) {
        return arguments.length ? (_alphaTarget = +_, simulation) : _alphaTarget;
      },
      velocityDecay: function velocityDecay(_) {
        return arguments.length ? (_velocityDecay = 1 - _, simulation) : 1 - _velocityDecay;
      },
      force: function force(name, _) {
        return arguments.length > 1 ? (_ == null ? forces.remove(name) : forces.set(name, initializeForce(_)), simulation) : forces.get(name);
      },
      find: function find(x, y, radius) {
        var i = 0,
            n = _nodes.length,
            dx,
            dy,
            d2,
            node,
            closest;
        if (radius == null) radius = Infinity;else radius *= radius;

        for (i = 0; i < n; ++i) {
          node = _nodes[i];
          dx = x - node.x;
          dy = y - node.y;
          d2 = dx * dx + dy * dy;
          if (d2 < radius) closest = node, radius = d2;
        }

        return closest;
      },
      on: function on(name, _) {
        return arguments.length > 1 ? (event.on(name, _), simulation) : event.on(name);
      }
    };
  }

  function manyBody () {
    var nodes,
        node,
        alpha,
        strength = constant$7(-30),
        strengths,
        distanceMin2 = 1,
        distanceMax2 = Infinity,
        theta2 = 0.81;

    function force(_) {
      var i,
          n = nodes.length,
          tree = quadtree(nodes, x$1, y$1).visitAfter(accumulate);

      for (alpha = _, i = 0; i < n; ++i) {
        node = nodes[i], tree.visit(apply);
      }
    }

    function initialize() {
      if (!nodes) return;
      var i,
          n = nodes.length,
          node;
      strengths = new Array(n);

      for (i = 0; i < n; ++i) {
        node = nodes[i], strengths[node.index] = +strength(node, i, nodes);
      }
    }

    function accumulate(quad) {
      var strength = 0,
          q,
          c,
          weight = 0,
          x,
          y,
          i; // For internal nodes, accumulate forces from child quadrants.

      if (quad.length) {
        for (x = y = i = 0; i < 4; ++i) {
          if ((q = quad[i]) && (c = Math.abs(q.value))) {
            strength += q.value, weight += c, x += c * q.x, y += c * q.y;
          }
        }

        quad.x = x / weight;
        quad.y = y / weight;
      } // For leaf nodes, accumulate forces from coincident quadrants.
      else {
          q = quad;
          q.x = q.data.x;
          q.y = q.data.y;

          do {
            strength += strengths[q.data.index];
          } while (q = q.next);
        }

      quad.value = strength;
    }

    function apply(quad, x1, _, x2) {
      if (!quad.value) return true;
      var x = quad.x - node.x,
          y = quad.y - node.y,
          w = x2 - x1,
          l = x * x + y * y; // Apply the Barnes-Hut approximation if possible.
      // Limit forces for very close nodes; randomize direction if coincident.

      if (w * w / theta2 < l) {
        if (l < distanceMax2) {
          if (x === 0) x = jiggle(), l += x * x;
          if (y === 0) y = jiggle(), l += y * y;
          if (l < distanceMin2) l = Math.sqrt(distanceMin2 * l);
          node.vx += x * quad.value * alpha / l;
          node.vy += y * quad.value * alpha / l;
        }

        return true;
      } // Otherwise, process points directly.
      else if (quad.length || l >= distanceMax2) return; // Limit forces for very close nodes; randomize direction if coincident.


      if (quad.data !== node || quad.next) {
        if (x === 0) x = jiggle(), l += x * x;
        if (y === 0) y = jiggle(), l += y * y;
        if (l < distanceMin2) l = Math.sqrt(distanceMin2 * l);
      }

      do {
        if (quad.data !== node) {
          w = strengths[quad.data.index] * alpha / l;
          node.vx += x * w;
          node.vy += y * w;
        }
      } while (quad = quad.next);
    }

    force.initialize = function (_) {
      nodes = _;
      initialize();
    };

    force.strength = function (_) {
      return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
    };

    force.distanceMin = function (_) {
      return arguments.length ? (distanceMin2 = _ * _, force) : Math.sqrt(distanceMin2);
    };

    force.distanceMax = function (_) {
      return arguments.length ? (distanceMax2 = _ * _, force) : Math.sqrt(distanceMax2);
    };

    force.theta = function (_) {
      return arguments.length ? (theta2 = _ * _, force) : Math.sqrt(theta2);
    };

    return force;
  }

  function radial (radius, x, y) {
    var nodes,
        strength = constant$7(0.1),
        strengths,
        radiuses;
    if (typeof radius !== "function") radius = constant$7(+radius);
    if (x == null) x = 0;
    if (y == null) y = 0;

    function force(alpha) {
      for (var i = 0, n = nodes.length; i < n; ++i) {
        var node = nodes[i],
            dx = node.x - x || 1e-6,
            dy = node.y - y || 1e-6,
            r = Math.sqrt(dx * dx + dy * dy),
            k = (radiuses[i] - r) * strengths[i] * alpha / r;
        node.vx += dx * k;
        node.vy += dy * k;
      }
    }

    function initialize() {
      if (!nodes) return;
      var i,
          n = nodes.length;
      strengths = new Array(n);
      radiuses = new Array(n);

      for (i = 0; i < n; ++i) {
        radiuses[i] = +radius(nodes[i], i, nodes);
        strengths[i] = isNaN(radiuses[i]) ? 0 : +strength(nodes[i], i, nodes);
      }
    }

    force.initialize = function (_) {
      nodes = _, initialize();
    };

    force.strength = function (_) {
      return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
    };

    force.radius = function (_) {
      return arguments.length ? (radius = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : radius;
    };

    force.x = function (_) {
      return arguments.length ? (x = +_, force) : x;
    };

    force.y = function (_) {
      return arguments.length ? (y = +_, force) : y;
    };

    return force;
  }

  function x$2 (x) {
    var strength = constant$7(0.1),
        nodes,
        strengths,
        xz;
    if (typeof x !== "function") x = constant$7(x == null ? 0 : +x);

    function force(alpha) {
      for (var i = 0, n = nodes.length, node; i < n; ++i) {
        node = nodes[i], node.vx += (xz[i] - node.x) * strengths[i] * alpha;
      }
    }

    function initialize() {
      if (!nodes) return;
      var i,
          n = nodes.length;
      strengths = new Array(n);
      xz = new Array(n);

      for (i = 0; i < n; ++i) {
        strengths[i] = isNaN(xz[i] = +x(nodes[i], i, nodes)) ? 0 : +strength(nodes[i], i, nodes);
      }
    }

    force.initialize = function (_) {
      nodes = _;
      initialize();
    };

    force.strength = function (_) {
      return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
    };

    force.x = function (_) {
      return arguments.length ? (x = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : x;
    };

    return force;
  }

  function y$2 (y) {
    var strength = constant$7(0.1),
        nodes,
        strengths,
        yz;
    if (typeof y !== "function") y = constant$7(y == null ? 0 : +y);

    function force(alpha) {
      for (var i = 0, n = nodes.length, node; i < n; ++i) {
        node = nodes[i], node.vy += (yz[i] - node.y) * strengths[i] * alpha;
      }
    }

    function initialize() {
      if (!nodes) return;
      var i,
          n = nodes.length;
      strengths = new Array(n);
      yz = new Array(n);

      for (i = 0; i < n; ++i) {
        strengths[i] = isNaN(yz[i] = +y(nodes[i], i, nodes)) ? 0 : +strength(nodes[i], i, nodes);
      }
    }

    force.initialize = function (_) {
      nodes = _;
      initialize();
    };

    force.strength = function (_) {
      return arguments.length ? (strength = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : strength;
    };

    force.y = function (_) {
      return arguments.length ? (y = typeof _ === "function" ? _ : constant$7(+_), initialize(), force) : y;
    };

    return force;
  }

  // Computes the decimal coefficient and exponent of the specified number x with
  // significant digits p, where x is positive and p is in [1, 21] or undefined.
  function formatDecimal (x, p) {
    if ((i = (x = p ? x.toExponential(p - 1) : x.toExponential()).indexOf("e")) < 0) return null; // NaN, В±Infinity

    var i,
        coefficient = x.slice(0, i); // The string returned by toExponential either has the form \d\.\d+e[-+]\d+
    // (e.g., 1.2e+3) or the form \de[-+]\d+ (e.g., 1e+3).

    return [coefficient.length > 1 ? coefficient[0] + coefficient.slice(2) : coefficient, +x.slice(i + 1)];
  }

  function exponent$1 (x) {
    return x = formatDecimal(Math.abs(x)), x ? x[1] : NaN;
  }

  function formatGroup (grouping, thousands) {
    return function (value, width) {
      var i = value.length,
          t = [],
          j = 0,
          g = grouping[0],
          length = 0;

      while (i > 0 && g > 0) {
        if (length + g + 1 > width) g = Math.max(1, width - length);
        t.push(value.substring(i -= g, i + g));
        if ((length += g + 1) > width) break;
        g = grouping[j = (j + 1) % grouping.length];
      }

      return t.reverse().join(thousands);
    };
  }

  function formatNumerals (numerals) {
    return function (value) {
      return value.replace(/[0-9]/g, function (i) {
        return numerals[+i];
      });
    };
  }

  // [[fill]align][sign][symbol][0][width][,][.precision][~][type]
  var re = /^(?:(.)?([<>=^]))?([+\-( ])?([$#])?(0)?(\d+)?(,)?(\.\d+)?(~)?([a-z%])?$/i;
  function formatSpecifier(specifier) {
    return new FormatSpecifier(specifier);
  }
  formatSpecifier.prototype = FormatSpecifier.prototype; // instanceof

  function FormatSpecifier(specifier) {
    if (!(match = re.exec(specifier))) throw new Error("invalid format: " + specifier);
    var match;
    this.fill = match[1] || " ";
    this.align = match[2] || ">";
    this.sign = match[3] || "-";
    this.symbol = match[4] || "";
    this.zero = !!match[5];
    this.width = match[6] && +match[6];
    this.comma = !!match[7];
    this.precision = match[8] && +match[8].slice(1);
    this.trim = !!match[9];
    this.type = match[10] || "";
  }

  FormatSpecifier.prototype.toString = function () {
    return this.fill + this.align + this.sign + this.symbol + (this.zero ? "0" : "") + (this.width == null ? "" : Math.max(1, this.width | 0)) + (this.comma ? "," : "") + (this.precision == null ? "" : "." + Math.max(0, this.precision | 0)) + (this.trim ? "~" : "") + this.type;
  };

  // Trims insignificant zeros, e.g., replaces 1.2000k with 1.2k.
  function formatTrim (s) {
    out: for (var n = s.length, i = 1, i0 = -1, i1; i < n; ++i) {
      switch (s[i]) {
        case ".":
          i0 = i1 = i;
          break;

        case "0":
          if (i0 === 0) i0 = i;
          i1 = i;
          break;

        default:
          if (i0 > 0) {
            if (!+s[i]) break out;
            i0 = 0;
          }

          break;
      }
    }

    return i0 > 0 ? s.slice(0, i0) + s.slice(i1 + 1) : s;
  }

  var prefixExponent;
  function formatPrefixAuto (x, p) {
    var d = formatDecimal(x, p);
    if (!d) return x + "";
    var coefficient = d[0],
        exponent = d[1],
        i = exponent - (prefixExponent = Math.max(-8, Math.min(8, Math.floor(exponent / 3))) * 3) + 1,
        n = coefficient.length;
    return i === n ? coefficient : i > n ? coefficient + new Array(i - n + 1).join("0") : i > 0 ? coefficient.slice(0, i) + "." + coefficient.slice(i) : "0." + new Array(1 - i).join("0") + formatDecimal(x, Math.max(0, p + i - 1))[0]; // less than 1y!
  }

  function formatRounded (x, p) {
    var d = formatDecimal(x, p);
    if (!d) return x + "";
    var coefficient = d[0],
        exponent = d[1];
    return exponent < 0 ? "0." + new Array(-exponent).join("0") + coefficient : coefficient.length > exponent + 1 ? coefficient.slice(0, exponent + 1) + "." + coefficient.slice(exponent + 1) : coefficient + new Array(exponent - coefficient.length + 2).join("0");
  }

  var formatTypes = {
    "%": function _(x, p) {
      return (x * 100).toFixed(p);
    },
    "b": function b(x) {
      return Math.round(x).toString(2);
    },
    "c": function c(x) {
      return x + "";
    },
    "d": function d(x) {
      return Math.round(x).toString(10);
    },
    "e": function e(x, p) {
      return x.toExponential(p);
    },
    "f": function f(x, p) {
      return x.toFixed(p);
    },
    "g": function g(x, p) {
      return x.toPrecision(p);
    },
    "o": function o(x) {
      return Math.round(x).toString(8);
    },
    "p": function p(x, _p) {
      return formatRounded(x * 100, _p);
    },
    "r": formatRounded,
    "s": formatPrefixAuto,
    "X": function X(x) {
      return Math.round(x).toString(16).toUpperCase();
    },
    "x": function x(_x) {
      return Math.round(_x).toString(16);
    }
  };

  function identity$3 (x) {
    return x;
  }

  var prefixes = ["y", "z", "a", "f", "p", "n", "µ", "m", "", "k", "M", "G", "T", "P", "E", "Z", "Y"];
  function formatLocale (locale) {
    var group = locale.grouping && locale.thousands ? formatGroup(locale.grouping, locale.thousands) : identity$3,
        currency = locale.currency,
        decimal = locale.decimal,
        numerals = locale.numerals ? formatNumerals(locale.numerals) : identity$3,
        percent = locale.percent || "%";

    function newFormat(specifier) {
      specifier = formatSpecifier(specifier);
      var fill = specifier.fill,
          align = specifier.align,
          sign = specifier.sign,
          symbol = specifier.symbol,
          zero = specifier.zero,
          width = specifier.width,
          comma = specifier.comma,
          precision = specifier.precision,
          trim = specifier.trim,
          type = specifier.type; // The "n" type is an alias for ",g".

      if (type === "n") comma = true, type = "g"; // The "" type, and any invalid type, is an alias for ".12~g".
      else if (!formatTypes[type]) precision == null && (precision = 12), trim = true, type = "g"; // If zero fill is specified, padding goes after sign and before digits.

      if (zero || fill === "0" && align === "=") zero = true, fill = "0", align = "="; // Compute the prefix and suffix.
      // For SI-prefix, the suffix is lazily computed.

      var prefix = symbol === "$" ? currency[0] : symbol === "#" && /[boxX]/.test(type) ? "0" + type.toLowerCase() : "",
          suffix = symbol === "$" ? currency[1] : /[%p]/.test(type) ? percent : ""; // What format function should we use?
      // Is this an integer type?
      // Can this type generate exponential notation?

      var formatType = formatTypes[type],
          maybeSuffix = /[defgprs%]/.test(type); // Set the default precision if not specified,
      // or clamp the specified precision to the supported range.
      // For significant precision, it must be in [1, 21].
      // For fixed precision, it must be in [0, 20].

      precision = precision == null ? 6 : /[gprs]/.test(type) ? Math.max(1, Math.min(21, precision)) : Math.max(0, Math.min(20, precision));

      function format(value) {
        var valuePrefix = prefix,
            valueSuffix = suffix,
            i,
            n,
            c;

        if (type === "c") {
          valueSuffix = formatType(value) + valueSuffix;
          value = "";
        } else {
          value = +value; // Perform the initial formatting.

          var valueNegative = value < 0;
          value = formatType(Math.abs(value), precision); // Trim insignificant zeros.

          if (trim) value = formatTrim(value); // If a negative value rounds to zero during formatting, treat as positive.

          if (valueNegative && +value === 0) valueNegative = false; // Compute the prefix and suffix.

          valuePrefix = (valueNegative ? sign === "(" ? sign : "-" : sign === "-" || sign === "(" ? "" : sign) + valuePrefix;
          valueSuffix = (type === "s" ? prefixes[8 + prefixExponent / 3] : "") + valueSuffix + (valueNegative && sign === "(" ? ")" : ""); // Break the formatted value into the integer “value” part that can be
          // grouped, and fractional or exponential “suffix” part that is not.

          if (maybeSuffix) {
            i = -1, n = value.length;

            while (++i < n) {
              if (c = value.charCodeAt(i), 48 > c || c > 57) {
                valueSuffix = (c === 46 ? decimal + value.slice(i + 1) : value.slice(i)) + valueSuffix;
                value = value.slice(0, i);
                break;
              }
            }
          }
        } // If the fill character is not "0", grouping is applied before padding.


        if (comma && !zero) value = group(value, Infinity); // Compute the padding.

        var length = valuePrefix.length + value.length + valueSuffix.length,
            padding = length < width ? new Array(width - length + 1).join(fill) : ""; // If the fill character is "0", grouping is applied after padding.

        if (comma && zero) value = group(padding + value, padding.length ? width - valueSuffix.length : Infinity), padding = ""; // Reconstruct the final output based on the desired alignment.

        switch (align) {
          case "<":
            value = valuePrefix + value + valueSuffix + padding;
            break;

          case "=":
            value = valuePrefix + padding + value + valueSuffix;
            break;

          case "^":
            value = padding.slice(0, length = padding.length >> 1) + valuePrefix + value + valueSuffix + padding.slice(length);
            break;

          default:
            value = padding + valuePrefix + value + valueSuffix;
            break;
        }

        return numerals(value);
      }

      format.toString = function () {
        return specifier + "";
      };

      return format;
    }

    function formatPrefix(specifier, value) {
      var f = newFormat((specifier = formatSpecifier(specifier), specifier.type = "f", specifier)),
          e = Math.max(-8, Math.min(8, Math.floor(exponent$1(value) / 3))) * 3,
          k = Math.pow(10, -e),
          prefix = prefixes[8 + e / 3];
      return function (value) {
        return f(k * value) + prefix;
      };
    }

    return {
      format: newFormat,
      formatPrefix: formatPrefix
    };
  }

  var locale;
  defaultLocale({
    decimal: ".",
    thousands: ",",
    grouping: [3],
    currency: ["$", ""]
  });
  function defaultLocale(definition) {
    locale = formatLocale(definition);
    exports.format = locale.format;
    exports.formatPrefix = locale.formatPrefix;
    return locale;
  }

  function precisionFixed (step) {
    return Math.max(0, -exponent$1(Math.abs(step)));
  }

  function precisionPrefix (step, value) {
    return Math.max(0, Math.max(-8, Math.min(8, Math.floor(exponent$1(value) / 3))) * 3 - exponent$1(Math.abs(step)));
  }

  function precisionRound (step, max) {
    step = Math.abs(step), max = Math.abs(max) - step;
    return Math.max(0, exponent$1(max) - exponent$1(step)) + 1;
  }

  // Adds floating point numbers with twice the normal precision.
  // Reference: J. R. Shewchuk, Adaptive Precision Floating-Point Arithmetic and
  // Fast Robust Geometric Predicates, Discrete & Computational Geometry 18(3)
  // 305вЂ“363 (1997).
  // Code adapted from GeographicLib by Charles F. F. Karney,
  // http://geographiclib.sourceforge.net/
  function adder () {
    return new Adder();
  }

  function Adder() {
    this.reset();
  }

  Adder.prototype = {
    constructor: Adder,
    reset: function reset() {
      this.s = // rounded value
      this.t = 0; // exact error
    },
    add: function add(y) {
      _add(temp, y, this.t);

      _add(this, temp.s, this.s);

      if (this.s) this.t += temp.t;else this.s = temp.t;
    },
    valueOf: function valueOf() {
      return this.s;
    }
  };
  var temp = new Adder();

  function _add(adder, a, b) {
    var x = adder.s = a + b,
        bv = x - a,
        av = x - bv;
    adder.t = a - av + (b - bv);
  }

  var epsilon$2 = 1e-6;
  var epsilon2$1 = 1e-12;
  var pi$3 = Math.PI;
  var halfPi$2 = pi$3 / 2;
  var quarterPi = pi$3 / 4;
  var tau$3 = pi$3 * 2;
  var degrees$1 = 180 / pi$3;
  var radians = pi$3 / 180;
  var abs = Math.abs;
  var atan = Math.atan;
  var atan2 = Math.atan2;
  var cos$1 = Math.cos;
  var ceil = Math.ceil;
  var exp = Math.exp;
  var log = Math.log;
  var pow = Math.pow;
  var sin$1 = Math.sin;
  var sign = Math.sign || function (x) {
    return x > 0 ? 1 : x < 0 ? -1 : 0;
  };
  var sqrt = Math.sqrt;
  var tan = Math.tan;
  function acos(x) {
    return x > 1 ? 0 : x < -1 ? pi$3 : Math.acos(x);
  }
  function asin(x) {
    return x > 1 ? halfPi$2 : x < -1 ? -halfPi$2 : Math.asin(x);
  }
  function haversin(x) {
    return (x = sin$1(x / 2)) * x;
  }

  function noop$2() {}

  function streamGeometry(geometry, stream) {
    if (geometry && streamGeometryType.hasOwnProperty(geometry.type)) {
      streamGeometryType[geometry.type](geometry, stream);
    }
  }

  var streamObjectType = {
    Feature: function Feature(object, stream) {
      streamGeometry(object.geometry, stream);
    },
    FeatureCollection: function FeatureCollection(object, stream) {
      var features = object.features,
          i = -1,
          n = features.length;

      while (++i < n) {
        streamGeometry(features[i].geometry, stream);
      }
    }
  };
  var streamGeometryType = {
    Sphere: function Sphere(object, stream) {
      stream.sphere();
    },
    Point: function Point(object, stream) {
      object = object.coordinates;
      stream.point(object[0], object[1], object[2]);
    },
    MultiPoint: function MultiPoint(object, stream) {
      var coordinates = object.coordinates,
          i = -1,
          n = coordinates.length;

      while (++i < n) {
        object = coordinates[i], stream.point(object[0], object[1], object[2]);
      }
    },
    LineString: function LineString(object, stream) {
      streamLine(object.coordinates, stream, 0);
    },
    MultiLineString: function MultiLineString(object, stream) {
      var coordinates = object.coordinates,
          i = -1,
          n = coordinates.length;

      while (++i < n) {
        streamLine(coordinates[i], stream, 0);
      }
    },
    Polygon: function Polygon(object, stream) {
      streamPolygon(object.coordinates, stream);
    },
    MultiPolygon: function MultiPolygon(object, stream) {
      var coordinates = object.coordinates,
          i = -1,
          n = coordinates.length;

      while (++i < n) {
        streamPolygon(coordinates[i], stream);
      }
    },
    GeometryCollection: function GeometryCollection(object, stream) {
      var geometries = object.geometries,
          i = -1,
          n = geometries.length;

      while (++i < n) {
        streamGeometry(geometries[i], stream);
      }
    }
  };

  function streamLine(coordinates, stream, closed) {
    var i = -1,
        n = coordinates.length - closed,
        coordinate;
    stream.lineStart();

    while (++i < n) {
      coordinate = coordinates[i], stream.point(coordinate[0], coordinate[1], coordinate[2]);
    }

    stream.lineEnd();
  }

  function streamPolygon(coordinates, stream) {
    var i = -1,
        n = coordinates.length;
    stream.polygonStart();

    while (++i < n) {
      streamLine(coordinates[i], stream, 1);
    }

    stream.polygonEnd();
  }

  function geoStream (object, stream) {
    if (object && streamObjectType.hasOwnProperty(object.type)) {
      streamObjectType[object.type](object, stream);
    } else {
      streamGeometry(object, stream);
    }
  }

  var areaRingSum = adder();
  var areaSum = adder(),
      lambda00,
      phi00,
      lambda0,
      cosPhi0,
      sinPhi0;
  var areaStream = {
    point: noop$2,
    lineStart: noop$2,
    lineEnd: noop$2,
    polygonStart: function polygonStart() {
      areaRingSum.reset();
      areaStream.lineStart = areaRingStart;
      areaStream.lineEnd = areaRingEnd;
    },
    polygonEnd: function polygonEnd() {
      var areaRing = +areaRingSum;
      areaSum.add(areaRing < 0 ? tau$3 + areaRing : areaRing);
      this.lineStart = this.lineEnd = this.point = noop$2;
    },
    sphere: function sphere() {
      areaSum.add(tau$3);
    }
  };

  function areaRingStart() {
    areaStream.point = areaPointFirst;
  }

  function areaRingEnd() {
    areaPoint(lambda00, phi00);
  }

  function areaPointFirst(lambda, phi) {
    areaStream.point = areaPoint;
    lambda00 = lambda, phi00 = phi;
    lambda *= radians, phi *= radians;
    lambda0 = lambda, cosPhi0 = cos$1(phi = phi / 2 + quarterPi), sinPhi0 = sin$1(phi);
  }

  function areaPoint(lambda, phi) {
    lambda *= radians, phi *= radians;
    phi = phi / 2 + quarterPi; // half the angular distance from south pole
    // Spherical excess E for a spherical triangle with vertices: south pole,
    // previous point, current point.  Uses a formula derived from CagnoliвЂ™s
    // theorem.  See Todhunter, Spherical Trig. (1871), Sec. 103, Eq. (2).

    var dLambda = lambda - lambda0,
        sdLambda = dLambda >= 0 ? 1 : -1,
        adLambda = sdLambda * dLambda,
        cosPhi = cos$1(phi),
        sinPhi = sin$1(phi),
        k = sinPhi0 * sinPhi,
        u = cosPhi0 * cosPhi + k * cos$1(adLambda),
        v = k * sdLambda * sin$1(adLambda);
    areaRingSum.add(atan2(v, u)); // Advance the previous points.

    lambda0 = lambda, cosPhi0 = cosPhi, sinPhi0 = sinPhi;
  }

  function area$1 (object) {
    areaSum.reset();
    geoStream(object, areaStream);
    return areaSum * 2;
  }

  function spherical(cartesian) {
    return [atan2(cartesian[1], cartesian[0]), asin(cartesian[2])];
  }
  function cartesian(spherical) {
    var lambda = spherical[0],
        phi = spherical[1],
        cosPhi = cos$1(phi);
    return [cosPhi * cos$1(lambda), cosPhi * sin$1(lambda), sin$1(phi)];
  }
  function cartesianDot(a, b) {
    return a[0] * b[0] + a[1] * b[1] + a[2] * b[2];
  }
  function cartesianCross(a, b) {
    return [a[1] * b[2] - a[2] * b[1], a[2] * b[0] - a[0] * b[2], a[0] * b[1] - a[1] * b[0]];
  } // TODO return a

  function cartesianAddInPlace(a, b) {
    a[0] += b[0], a[1] += b[1], a[2] += b[2];
  }
  function cartesianScale(vector, k) {
    return [vector[0] * k, vector[1] * k, vector[2] * k];
  } // TODO return d

  function cartesianNormalizeInPlace(d) {
    var l = sqrt(d[0] * d[0] + d[1] * d[1] + d[2] * d[2]);
    d[0] /= l, d[1] /= l, d[2] /= l;
  }

  var lambda0$1,
      phi0,
      lambda1,
      phi1,
      // bounds
  lambda2,
      // previous lambda-coordinate
  lambda00$1,
      phi00$1,
      // first point
  p0,
      // previous 3D point
  deltaSum = adder(),
      ranges,
      range;
  var boundsStream = {
    point: boundsPoint,
    lineStart: boundsLineStart,
    lineEnd: boundsLineEnd,
    polygonStart: function polygonStart() {
      boundsStream.point = boundsRingPoint;
      boundsStream.lineStart = boundsRingStart;
      boundsStream.lineEnd = boundsRingEnd;
      deltaSum.reset();
      areaStream.polygonStart();
    },
    polygonEnd: function polygonEnd() {
      areaStream.polygonEnd();
      boundsStream.point = boundsPoint;
      boundsStream.lineStart = boundsLineStart;
      boundsStream.lineEnd = boundsLineEnd;
      if (areaRingSum < 0) lambda0$1 = -(lambda1 = 180), phi0 = -(phi1 = 90);else if (deltaSum > epsilon$2) phi1 = 90;else if (deltaSum < -epsilon$2) phi0 = -90;
      range[0] = lambda0$1, range[1] = lambda1;
    }
  };

  function boundsPoint(lambda, phi) {
    ranges.push(range = [lambda0$1 = lambda, lambda1 = lambda]);
    if (phi < phi0) phi0 = phi;
    if (phi > phi1) phi1 = phi;
  }

  function linePoint(lambda, phi) {
    var p = cartesian([lambda * radians, phi * radians]);

    if (p0) {
      var normal = cartesianCross(p0, p),
          equatorial = [normal[1], -normal[0], 0],
          inflection = cartesianCross(equatorial, normal);
      cartesianNormalizeInPlace(inflection);
      inflection = spherical(inflection);
      var delta = lambda - lambda2,
          sign$$1 = delta > 0 ? 1 : -1,
          lambdai = inflection[0] * degrees$1 * sign$$1,
          phii,
          antimeridian = abs(delta) > 180;

      if (antimeridian ^ (sign$$1 * lambda2 < lambdai && lambdai < sign$$1 * lambda)) {
        phii = inflection[1] * degrees$1;
        if (phii > phi1) phi1 = phii;
      } else if (lambdai = (lambdai + 360) % 360 - 180, antimeridian ^ (sign$$1 * lambda2 < lambdai && lambdai < sign$$1 * lambda)) {
        phii = -inflection[1] * degrees$1;
        if (phii < phi0) phi0 = phii;
      } else {
        if (phi < phi0) phi0 = phi;
        if (phi > phi1) phi1 = phi;
      }

      if (antimeridian) {
        if (lambda < lambda2) {
          if (angle(lambda0$1, lambda) > angle(lambda0$1, lambda1)) lambda1 = lambda;
        } else {
          if (angle(lambda, lambda1) > angle(lambda0$1, lambda1)) lambda0$1 = lambda;
        }
      } else {
        if (lambda1 >= lambda0$1) {
          if (lambda < lambda0$1) lambda0$1 = lambda;
          if (lambda > lambda1) lambda1 = lambda;
        } else {
          if (lambda > lambda2) {
            if (angle(lambda0$1, lambda) > angle(lambda0$1, lambda1)) lambda1 = lambda;
          } else {
            if (angle(lambda, lambda1) > angle(lambda0$1, lambda1)) lambda0$1 = lambda;
          }
        }
      }
    } else {
      ranges.push(range = [lambda0$1 = lambda, lambda1 = lambda]);
    }

    if (phi < phi0) phi0 = phi;
    if (phi > phi1) phi1 = phi;
    p0 = p, lambda2 = lambda;
  }

  function boundsLineStart() {
    boundsStream.point = linePoint;
  }

  function boundsLineEnd() {
    range[0] = lambda0$1, range[1] = lambda1;
    boundsStream.point = boundsPoint;
    p0 = null;
  }

  function boundsRingPoint(lambda, phi) {
    if (p0) {
      var delta = lambda - lambda2;
      deltaSum.add(abs(delta) > 180 ? delta + (delta > 0 ? 360 : -360) : delta);
    } else {
      lambda00$1 = lambda, phi00$1 = phi;
    }

    areaStream.point(lambda, phi);
    linePoint(lambda, phi);
  }

  function boundsRingStart() {
    areaStream.lineStart();
  }

  function boundsRingEnd() {
    boundsRingPoint(lambda00$1, phi00$1);
    areaStream.lineEnd();
    if (abs(deltaSum) > epsilon$2) lambda0$1 = -(lambda1 = 180);
    range[0] = lambda0$1, range[1] = lambda1;
    p0 = null;
  } // Finds the left-right distance between two longitudes.
  // This is almost the same as (lambda1 - lambda0 + 360°) % 360°, except that we want
  // the distance between ±180° to be 360°.


  function angle(lambda0, lambda1) {
    return (lambda1 -= lambda0) < 0 ? lambda1 + 360 : lambda1;
  }

  function rangeCompare(a, b) {
    return a[0] - b[0];
  }

  function rangeContains(range, x) {
    return range[0] <= range[1] ? range[0] <= x && x <= range[1] : x < range[0] || range[1] < x;
  }

  function bounds (feature) {
    var i, n, a, b, merged, deltaMax, delta;
    phi1 = lambda1 = -(lambda0$1 = phi0 = Infinity);
    ranges = [];
    geoStream(feature, boundsStream); // First, sort ranges by their minimum longitudes.

    if (n = ranges.length) {
      ranges.sort(rangeCompare); // Then, merge any ranges that overlap.

      for (i = 1, a = ranges[0], merged = [a]; i < n; ++i) {
        b = ranges[i];

        if (rangeContains(a, b[0]) || rangeContains(a, b[1])) {
          if (angle(a[0], b[1]) > angle(a[0], a[1])) a[1] = b[1];
          if (angle(b[0], a[1]) > angle(a[0], a[1])) a[0] = b[0];
        } else {
          merged.push(a = b);
        }
      } // Finally, find the largest gap between the merged ranges.
      // The final bounding box will be the inverse of this gap.


      for (deltaMax = -Infinity, n = merged.length - 1, i = 0, a = merged[n]; i <= n; a = b, ++i) {
        b = merged[i];
        if ((delta = angle(a[1], b[0])) > deltaMax) deltaMax = delta, lambda0$1 = b[0], lambda1 = a[1];
      }
    }

    ranges = range = null;
    return lambda0$1 === Infinity || phi0 === Infinity ? [[NaN, NaN], [NaN, NaN]] : [[lambda0$1, phi0], [lambda1, phi1]];
  }

  var W0, W1, X0, Y0, Z0, X1, Y1, Z1, X2, Y2, Z2, lambda00$2, phi00$2, // first point
  x0, y0, z0; // previous point

  var centroidStream = {
    sphere: noop$2,
    point: centroidPoint,
    lineStart: centroidLineStart,
    lineEnd: centroidLineEnd,
    polygonStart: function polygonStart() {
      centroidStream.lineStart = centroidRingStart;
      centroidStream.lineEnd = centroidRingEnd;
    },
    polygonEnd: function polygonEnd() {
      centroidStream.lineStart = centroidLineStart;
      centroidStream.lineEnd = centroidLineEnd;
    }
  }; // Arithmetic mean of Cartesian vectors.

  function centroidPoint(lambda, phi) {
    lambda *= radians, phi *= radians;
    var cosPhi = cos$1(phi);
    centroidPointCartesian(cosPhi * cos$1(lambda), cosPhi * sin$1(lambda), sin$1(phi));
  }

  function centroidPointCartesian(x, y, z) {
    ++W0;
    X0 += (x - X0) / W0;
    Y0 += (y - Y0) / W0;
    Z0 += (z - Z0) / W0;
  }

  function centroidLineStart() {
    centroidStream.point = centroidLinePointFirst;
  }

  function centroidLinePointFirst(lambda, phi) {
    lambda *= radians, phi *= radians;
    var cosPhi = cos$1(phi);
    x0 = cosPhi * cos$1(lambda);
    y0 = cosPhi * sin$1(lambda);
    z0 = sin$1(phi);
    centroidStream.point = centroidLinePoint;
    centroidPointCartesian(x0, y0, z0);
  }

  function centroidLinePoint(lambda, phi) {
    lambda *= radians, phi *= radians;
    var cosPhi = cos$1(phi),
        x = cosPhi * cos$1(lambda),
        y = cosPhi * sin$1(lambda),
        z = sin$1(phi),
        w = atan2(sqrt((w = y0 * z - z0 * y) * w + (w = z0 * x - x0 * z) * w + (w = x0 * y - y0 * x) * w), x0 * x + y0 * y + z0 * z);
    W1 += w;
    X1 += w * (x0 + (x0 = x));
    Y1 += w * (y0 + (y0 = y));
    Z1 += w * (z0 + (z0 = z));
    centroidPointCartesian(x0, y0, z0);
  }

  function centroidLineEnd() {
    centroidStream.point = centroidPoint;
  } // See J. E. Brock, The Inertia Tensor for a Spherical Triangle,
  // J. Applied Mechanics 42, 239 (1975).


  function centroidRingStart() {
    centroidStream.point = centroidRingPointFirst;
  }

  function centroidRingEnd() {
    centroidRingPoint(lambda00$2, phi00$2);
    centroidStream.point = centroidPoint;
  }

  function centroidRingPointFirst(lambda, phi) {
    lambda00$2 = lambda, phi00$2 = phi;
    lambda *= radians, phi *= radians;
    centroidStream.point = centroidRingPoint;
    var cosPhi = cos$1(phi);
    x0 = cosPhi * cos$1(lambda);
    y0 = cosPhi * sin$1(lambda);
    z0 = sin$1(phi);
    centroidPointCartesian(x0, y0, z0);
  }

  function centroidRingPoint(lambda, phi) {
    lambda *= radians, phi *= radians;
    var cosPhi = cos$1(phi),
        x = cosPhi * cos$1(lambda),
        y = cosPhi * sin$1(lambda),
        z = sin$1(phi),
        cx = y0 * z - z0 * y,
        cy = z0 * x - x0 * z,
        cz = x0 * y - y0 * x,
        m = sqrt(cx * cx + cy * cy + cz * cz),
        w = asin(m),
        // line weight = angle
    v = m && -w / m; // area weight multiplier

    X2 += v * cx;
    Y2 += v * cy;
    Z2 += v * cz;
    W1 += w;
    X1 += w * (x0 + (x0 = x));
    Y1 += w * (y0 + (y0 = y));
    Z1 += w * (z0 + (z0 = z));
    centroidPointCartesian(x0, y0, z0);
  }

  function centroid (object) {
    W0 = W1 = X0 = Y0 = Z0 = X1 = Y1 = Z1 = X2 = Y2 = Z2 = 0;
    geoStream(object, centroidStream);
    var x = X2,
        y = Y2,
        z = Z2,
        m = x * x + y * y + z * z; // If the area-weighted ccentroid is undefined, fall back to length-weighted ccentroid.

    if (m < epsilon2$1) {
      x = X1, y = Y1, z = Z1; // If the feature has zero length, fall back to arithmetic mean of point vectors.

      if (W1 < epsilon$2) x = X0, y = Y0, z = Z0;
      m = x * x + y * y + z * z; // If the feature still has an undefined ccentroid, then return.

      if (m < epsilon2$1) return [NaN, NaN];
    }

    return [atan2(y, x) * degrees$1, asin(z / sqrt(m)) * degrees$1];
  }

  function constant$8 (x) {
    return function () {
      return x;
    };
  }

  function compose (a, b) {
    function compose(x, y) {
      return x = a(x, y), b(x[0], x[1]);
    }

    if (a.invert && b.invert) compose.invert = function (x, y) {
      return x = b.invert(x, y), x && a.invert(x[0], x[1]);
    };
    return compose;
  }

  function rotationIdentity(lambda, phi) {
    return [abs(lambda) > pi$3 ? lambda + Math.round(-lambda / tau$3) * tau$3 : lambda, phi];
  }

  rotationIdentity.invert = rotationIdentity;
  function rotateRadians(deltaLambda, deltaPhi, deltaGamma) {
    return (deltaLambda %= tau$3) ? deltaPhi || deltaGamma ? compose(rotationLambda(deltaLambda), rotationPhiGamma(deltaPhi, deltaGamma)) : rotationLambda(deltaLambda) : deltaPhi || deltaGamma ? rotationPhiGamma(deltaPhi, deltaGamma) : rotationIdentity;
  }

  function forwardRotationLambda(deltaLambda) {
    return function (lambda, phi) {
      return lambda += deltaLambda, [lambda > pi$3 ? lambda - tau$3 : lambda < -pi$3 ? lambda + tau$3 : lambda, phi];
    };
  }

  function rotationLambda(deltaLambda) {
    var rotation = forwardRotationLambda(deltaLambda);
    rotation.invert = forwardRotationLambda(-deltaLambda);
    return rotation;
  }

  function rotationPhiGamma(deltaPhi, deltaGamma) {
    var cosDeltaPhi = cos$1(deltaPhi),
        sinDeltaPhi = sin$1(deltaPhi),
        cosDeltaGamma = cos$1(deltaGamma),
        sinDeltaGamma = sin$1(deltaGamma);

    function rotation(lambda, phi) {
      var cosPhi = cos$1(phi),
          x = cos$1(lambda) * cosPhi,
          y = sin$1(lambda) * cosPhi,
          z = sin$1(phi),
          k = z * cosDeltaPhi + x * sinDeltaPhi;
      return [atan2(y * cosDeltaGamma - k * sinDeltaGamma, x * cosDeltaPhi - z * sinDeltaPhi), asin(k * cosDeltaGamma + y * sinDeltaGamma)];
    }

    rotation.invert = function (lambda, phi) {
      var cosPhi = cos$1(phi),
          x = cos$1(lambda) * cosPhi,
          y = sin$1(lambda) * cosPhi,
          z = sin$1(phi),
          k = z * cosDeltaGamma - y * sinDeltaGamma;
      return [atan2(y * cosDeltaGamma + z * sinDeltaGamma, x * cosDeltaPhi + k * sinDeltaPhi), asin(k * cosDeltaPhi - x * sinDeltaPhi)];
    };

    return rotation;
  }

  function rotation (rotate) {
    rotate = rotateRadians(rotate[0] * radians, rotate[1] * radians, rotate.length > 2 ? rotate[2] * radians : 0);

    function forward(coordinates) {
      coordinates = rotate(coordinates[0] * radians, coordinates[1] * radians);
      return coordinates[0] *= degrees$1, coordinates[1] *= degrees$1, coordinates;
    }

    forward.invert = function (coordinates) {
      coordinates = rotate.invert(coordinates[0] * radians, coordinates[1] * radians);
      return coordinates[0] *= degrees$1, coordinates[1] *= degrees$1, coordinates;
    };

    return forward;
  }

  function circleStream(stream, radius, delta, direction, t0, t1) {
    if (!delta) return;
    var cosRadius = cos$1(radius),
        sinRadius = sin$1(radius),
        step = direction * delta;

    if (t0 == null) {
      t0 = radius + direction * tau$3;
      t1 = radius - step / 2;
    } else {
      t0 = circleRadius(cosRadius, t0);
      t1 = circleRadius(cosRadius, t1);
      if (direction > 0 ? t0 < t1 : t0 > t1) t0 += direction * tau$3;
    }

    for (var point, t = t0; direction > 0 ? t > t1 : t < t1; t -= step) {
      point = spherical([cosRadius, -sinRadius * cos$1(t), -sinRadius * sin$1(t)]);
      stream.point(point[0], point[1]);
    }
  } // Returns the signed angle of a cartesian point relative to [cosRadius, 0, 0].

  function circleRadius(cosRadius, point) {
    point = cartesian(point), point[0] -= cosRadius;
    cartesianNormalizeInPlace(point);
    var radius = acos(-point[1]);
    return ((-point[2] < 0 ? -radius : radius) + tau$3 - epsilon$2) % tau$3;
  }

  function circle () {
    var center = constant$8([0, 0]),
        radius = constant$8(90),
        precision = constant$8(6),
        ring,
        rotate,
        stream = {
      point: point
    };

    function point(x, y) {
      ring.push(x = rotate(x, y));
      x[0] *= degrees$1, x[1] *= degrees$1;
    }

    function circle() {
      var c = center.apply(this, arguments),
          r = radius.apply(this, arguments) * radians,
          p = precision.apply(this, arguments) * radians;
      ring = [];
      rotate = rotateRadians(-c[0] * radians, -c[1] * radians, 0).invert;
      circleStream(stream, r, p, 1);
      c = {
        type: "Polygon",
        coordinates: [ring]
      };
      ring = rotate = null;
      return c;
    }

    circle.center = function (_) {
      return arguments.length ? (center = typeof _ === "function" ? _ : constant$8([+_[0], +_[1]]), circle) : center;
    };

    circle.radius = function (_) {
      return arguments.length ? (radius = typeof _ === "function" ? _ : constant$8(+_), circle) : radius;
    };

    circle.precision = function (_) {
      return arguments.length ? (precision = typeof _ === "function" ? _ : constant$8(+_), circle) : precision;
    };

    return circle;
  }

  function clipBuffer () {
    var lines = [],
        line;
    return {
      point: function point(x, y) {
        line.push([x, y]);
      },
      lineStart: function lineStart() {
        lines.push(line = []);
      },
      lineEnd: noop$2,
      rejoin: function rejoin() {
        if (lines.length > 1) lines.push(lines.pop().concat(lines.shift()));
      },
      result: function result() {
        var result = lines;
        lines = [];
        line = null;
        return result;
      }
    };
  }

  function pointEqual (a, b) {
    return abs(a[0] - b[0]) < epsilon$2 && abs(a[1] - b[1]) < epsilon$2;
  }

  function Intersection(point, points, other, entry) {
    this.x = point;
    this.z = points;
    this.o = other; // another intersection

    this.e = entry; // is an entry?

    this.v = false; // visited

    this.n = this.p = null; // next & previous
  } // A generalized polygon clipping algorithm: given a polygon that has been cut
  // into its visible line segments, and rejoins the segments by interpolating
  // along the clip edge.


  function clipRejoin (segments, compareIntersection, startInside, interpolate, stream) {
    var subject = [],
        clip = [],
        i,
        n;
    segments.forEach(function (segment) {
      if ((n = segment.length - 1) <= 0) return;
      var n,
          p0 = segment[0],
          p1 = segment[n],
          x; // If the first and last points of a segment are coincident, then treat as a
      // closed ring. TODO if all rings are closed, then the winding order of the
      // exterior ring should be checked.

      if (pointEqual(p0, p1)) {
        stream.lineStart();

        for (i = 0; i < n; ++i) {
          stream.point((p0 = segment[i])[0], p0[1]);
        }

        stream.lineEnd();
        return;
      }

      subject.push(x = new Intersection(p0, segment, null, true));
      clip.push(x.o = new Intersection(p0, null, x, false));
      subject.push(x = new Intersection(p1, segment, null, false));
      clip.push(x.o = new Intersection(p1, null, x, true));
    });
    if (!subject.length) return;
    clip.sort(compareIntersection);
    link$1(subject);
    link$1(clip);

    for (i = 0, n = clip.length; i < n; ++i) {
      clip[i].e = startInside = !startInside;
    }

    var start = subject[0],
        points,
        point;

    while (1) {
      // Find first unvisited intersection.
      var current = start,
          isSubject = true;

      while (current.v) {
        if ((current = current.n) === start) return;
      }

      points = current.z;
      stream.lineStart();

      do {
        current.v = current.o.v = true;

        if (current.e) {
          if (isSubject) {
            for (i = 0, n = points.length; i < n; ++i) {
              stream.point((point = points[i])[0], point[1]);
            }
          } else {
            interpolate(current.x, current.n.x, 1, stream);
          }

          current = current.n;
        } else {
          if (isSubject) {
            points = current.p.z;

            for (i = points.length - 1; i >= 0; --i) {
              stream.point((point = points[i])[0], point[1]);
            }
          } else {
            interpolate(current.x, current.p.x, -1, stream);
          }

          current = current.p;
        }

        current = current.o;
        points = current.z;
        isSubject = !isSubject;
      } while (!current.v);

      stream.lineEnd();
    }
  }

  function link$1(array) {
    if (!(n = array.length)) return;
    var n,
        i = 0,
        a = array[0],
        b;

    while (++i < n) {
      a.n = b = array[i];
      b.p = a;
      a = b;
    }

    a.n = b = array[0];
    b.p = a;
  }

  var sum$1 = adder();
  function polygonContains (polygon, point) {
    var lambda = point[0],
        phi = point[1],
        sinPhi = sin$1(phi),
        normal = [sin$1(lambda), -cos$1(lambda), 0],
        angle = 0,
        winding = 0;
    sum$1.reset();
    if (sinPhi === 1) phi = halfPi$2 + epsilon$2;else if (sinPhi === -1) phi = -halfPi$2 - epsilon$2;

    for (var i = 0, n = polygon.length; i < n; ++i) {
      if (!(m = (ring = polygon[i]).length)) continue;
      var ring,
          m,
          point0 = ring[m - 1],
          lambda0 = point0[0],
          phi0 = point0[1] / 2 + quarterPi,
          sinPhi0 = sin$1(phi0),
          cosPhi0 = cos$1(phi0);

      for (var j = 0; j < m; ++j, lambda0 = lambda1, sinPhi0 = sinPhi1, cosPhi0 = cosPhi1, point0 = point1) {
        var point1 = ring[j],
            lambda1 = point1[0],
            phi1 = point1[1] / 2 + quarterPi,
            sinPhi1 = sin$1(phi1),
            cosPhi1 = cos$1(phi1),
            delta = lambda1 - lambda0,
            sign$$1 = delta >= 0 ? 1 : -1,
            absDelta = sign$$1 * delta,
            antimeridian = absDelta > pi$3,
            k = sinPhi0 * sinPhi1;
        sum$1.add(atan2(k * sign$$1 * sin$1(absDelta), cosPhi0 * cosPhi1 + k * cos$1(absDelta)));
        angle += antimeridian ? delta + sign$$1 * tau$3 : delta; // Are the longitudes either side of the pointвЂ™s meridian (lambda),
        // and are the latitudes smaller than the parallel (phi)?

        if (antimeridian ^ lambda0 >= lambda ^ lambda1 >= lambda) {
          var arc = cartesianCross(cartesian(point0), cartesian(point1));
          cartesianNormalizeInPlace(arc);
          var intersection = cartesianCross(normal, arc);
          cartesianNormalizeInPlace(intersection);
          var phiArc = (antimeridian ^ delta >= 0 ? -1 : 1) * asin(intersection[2]);

          if (phi > phiArc || phi === phiArc && (arc[0] || arc[1])) {
            winding += antimeridian ^ delta >= 0 ? 1 : -1;
          }
        }
      }
    } // First, determine whether the South pole is inside or outside:
    //
    // It is inside if:
    // * the polygon winds around it in a clockwise direction.
    // * the polygon does not (cumulatively) wind around it, but has a negative
    //   (counter-clockwise) area.
    //
    // Second, count the (signed) number of times a segment crosses a lambda
    // from the point to the South pole.  If it is zero, then the point is the
    // same side as the South pole.


    return (angle < -epsilon$2 || angle < epsilon$2 && sum$1 < -epsilon$2) ^ winding & 1;
  }

  function clip (pointVisible, clipLine, interpolate, start) {
    return function (sink) {
      var line = clipLine(sink),
          ringBuffer = clipBuffer(),
          ringSink = clipLine(ringBuffer),
          polygonStarted = false,
          polygon,
          segments,
          ring;
      var clip = {
        point: point,
        lineStart: lineStart,
        lineEnd: lineEnd,
        polygonStart: function polygonStart() {
          clip.point = pointRing;
          clip.lineStart = ringStart;
          clip.lineEnd = ringEnd;
          segments = [];
          polygon = [];
        },
        polygonEnd: function polygonEnd() {
          clip.point = point;
          clip.lineStart = lineStart;
          clip.lineEnd = lineEnd;
          segments = merge(segments);
          var startInside = polygonContains(polygon, start);

          if (segments.length) {
            if (!polygonStarted) sink.polygonStart(), polygonStarted = true;
            clipRejoin(segments, compareIntersection, startInside, interpolate, sink);
          } else if (startInside) {
            if (!polygonStarted) sink.polygonStart(), polygonStarted = true;
            sink.lineStart();
            interpolate(null, null, 1, sink);
            sink.lineEnd();
          }

          if (polygonStarted) sink.polygonEnd(), polygonStarted = false;
          segments = polygon = null;
        },
        sphere: function sphere() {
          sink.polygonStart();
          sink.lineStart();
          interpolate(null, null, 1, sink);
          sink.lineEnd();
          sink.polygonEnd();
        }
      };

      function point(lambda, phi) {
        if (pointVisible(lambda, phi)) sink.point(lambda, phi);
      }

      function pointLine(lambda, phi) {
        line.point(lambda, phi);
      }

      function lineStart() {
        clip.point = pointLine;
        line.lineStart();
      }

      function lineEnd() {
        clip.point = point;
        line.lineEnd();
      }

      function pointRing(lambda, phi) {
        ring.push([lambda, phi]);
        ringSink.point(lambda, phi);
      }

      function ringStart() {
        ringSink.lineStart();
        ring = [];
      }

      function ringEnd() {
        pointRing(ring[0][0], ring[0][1]);
        ringSink.lineEnd();
        var clean = ringSink.clean(),
            ringSegments = ringBuffer.result(),
            i,
            n = ringSegments.length,
            m,
            segment,
            point;
        ring.pop();
        polygon.push(ring);
        ring = null;
        if (!n) return; // No intersections.

        if (clean & 1) {
          segment = ringSegments[0];

          if ((m = segment.length - 1) > 0) {
            if (!polygonStarted) sink.polygonStart(), polygonStarted = true;
            sink.lineStart();

            for (i = 0; i < m; ++i) {
              sink.point((point = segment[i])[0], point[1]);
            }

            sink.lineEnd();
          }

          return;
        } // Rejoin connected segments.
        // TODO reuse ringBuffer.rejoin()?


        if (n > 1 && clean & 2) ringSegments.push(ringSegments.pop().concat(ringSegments.shift()));
        segments.push(ringSegments.filter(validSegment));
      }

      return clip;
    };
  }

  function validSegment(segment) {
    return segment.length > 1;
  } // Intersections are sorted along the clip edge. For both antimeridian cutting
  // and circle clipping, the same comparison is used.


  function compareIntersection(a, b) {
    return ((a = a.x)[0] < 0 ? a[1] - halfPi$2 - epsilon$2 : halfPi$2 - a[1]) - ((b = b.x)[0] < 0 ? b[1] - halfPi$2 - epsilon$2 : halfPi$2 - b[1]);
  }

  var clipAntimeridian = clip(function () {
    return true;
  }, clipAntimeridianLine, clipAntimeridianInterpolate, [-pi$3, -halfPi$2]); // Takes a line and cuts into visible segments. Return values: 0 - there were
  // intersections or the line was empty; 1 - no intersections; 2 - there were
  // intersections, and the first and last segments should be rejoined.

  function clipAntimeridianLine(stream) {
    var lambda0 = NaN,
        phi0 = NaN,
        sign0 = NaN,
        _clean; // no intersections


    return {
      lineStart: function lineStart() {
        stream.lineStart();
        _clean = 1;
      },
      point: function point(lambda1, phi1) {
        var sign1 = lambda1 > 0 ? pi$3 : -pi$3,
            delta = abs(lambda1 - lambda0);

        if (abs(delta - pi$3) < epsilon$2) {
          // line crosses a pole
          stream.point(lambda0, phi0 = (phi0 + phi1) / 2 > 0 ? halfPi$2 : -halfPi$2);
          stream.point(sign0, phi0);
          stream.lineEnd();
          stream.lineStart();
          stream.point(sign1, phi0);
          stream.point(lambda1, phi0);
          _clean = 0;
        } else if (sign0 !== sign1 && delta >= pi$3) {
          // line crosses antimeridian
          if (abs(lambda0 - sign0) < epsilon$2) lambda0 -= sign0 * epsilon$2; // handle degeneracies

          if (abs(lambda1 - sign1) < epsilon$2) lambda1 -= sign1 * epsilon$2;
          phi0 = clipAntimeridianIntersect(lambda0, phi0, lambda1, phi1);
          stream.point(sign0, phi0);
          stream.lineEnd();
          stream.lineStart();
          stream.point(sign1, phi0);
          _clean = 0;
        }

        stream.point(lambda0 = lambda1, phi0 = phi1);
        sign0 = sign1;
      },
      lineEnd: function lineEnd() {
        stream.lineEnd();
        lambda0 = phi0 = NaN;
      },
      clean: function clean() {
        return 2 - _clean; // if intersections, rejoin first and last segments
      }
    };
  }

  function clipAntimeridianIntersect(lambda0, phi0, lambda1, phi1) {
    var cosPhi0,
        cosPhi1,
        sinLambda0Lambda1 = sin$1(lambda0 - lambda1);
    return abs(sinLambda0Lambda1) > epsilon$2 ? atan((sin$1(phi0) * (cosPhi1 = cos$1(phi1)) * sin$1(lambda1) - sin$1(phi1) * (cosPhi0 = cos$1(phi0)) * sin$1(lambda0)) / (cosPhi0 * cosPhi1 * sinLambda0Lambda1)) : (phi0 + phi1) / 2;
  }

  function clipAntimeridianInterpolate(from, to, direction, stream) {
    var phi;

    if (from == null) {
      phi = direction * halfPi$2;
      stream.point(-pi$3, phi);
      stream.point(0, phi);
      stream.point(pi$3, phi);
      stream.point(pi$3, 0);
      stream.point(pi$3, -phi);
      stream.point(0, -phi);
      stream.point(-pi$3, -phi);
      stream.point(-pi$3, 0);
      stream.point(-pi$3, phi);
    } else if (abs(from[0] - to[0]) > epsilon$2) {
      var lambda = from[0] < to[0] ? pi$3 : -pi$3;
      phi = direction * lambda / 2;
      stream.point(-lambda, phi);
      stream.point(0, phi);
      stream.point(lambda, phi);
    } else {
      stream.point(to[0], to[1]);
    }
  }

  function clipCircle (radius) {
    var cr = cos$1(radius),
        delta = 6 * radians,
        smallRadius = cr > 0,
        notHemisphere = abs(cr) > epsilon$2; // TODO optimise for this common case

    function interpolate(from, to, direction, stream) {
      circleStream(stream, radius, delta, direction, from, to);
    }

    function visible(lambda, phi) {
      return cos$1(lambda) * cos$1(phi) > cr;
    } // Takes a line and cuts into visible segments. Return values used for polygon
    // clipping: 0 - there were intersections or the line was empty; 1 - no
    // intersections 2 - there were intersections, and the first and last segments
    // should be rejoined.


    function clipLine(stream) {
      var point0, // previous point
      c0, // code for previous point
      v0, // visibility of previous point
      v00, // visibility of first point
      _clean; // no intersections


      return {
        lineStart: function lineStart() {
          v00 = v0 = false;
          _clean = 1;
        },
        point: function point(lambda, phi) {
          var point1 = [lambda, phi],
              point2,
              v = visible(lambda, phi),
              c = smallRadius ? v ? 0 : code(lambda, phi) : v ? code(lambda + (lambda < 0 ? pi$3 : -pi$3), phi) : 0;
          if (!point0 && (v00 = v0 = v)) stream.lineStart(); // Handle degeneracies.
          // TODO ignore if not clipping polygons.

          if (v !== v0) {
            point2 = intersect(point0, point1);

            if (!point2 || pointEqual(point0, point2) || pointEqual(point1, point2)) {
              point1[0] += epsilon$2;
              point1[1] += epsilon$2;
              v = visible(point1[0], point1[1]);
            }
          }

          if (v !== v0) {
            _clean = 0;

            if (v) {
              // outside going in
              stream.lineStart();
              point2 = intersect(point1, point0);
              stream.point(point2[0], point2[1]);
            } else {
              // inside going out
              point2 = intersect(point0, point1);
              stream.point(point2[0], point2[1]);
              stream.lineEnd();
            }

            point0 = point2;
          } else if (notHemisphere && point0 && smallRadius ^ v) {
            var t; // If the codes for two points are different, or are both zero,
            // and there this segment intersects with the small circle.

            if (!(c & c0) && (t = intersect(point1, point0, true))) {
              _clean = 0;

              if (smallRadius) {
                stream.lineStart();
                stream.point(t[0][0], t[0][1]);
                stream.point(t[1][0], t[1][1]);
                stream.lineEnd();
              } else {
                stream.point(t[1][0], t[1][1]);
                stream.lineEnd();
                stream.lineStart();
                stream.point(t[0][0], t[0][1]);
              }
            }
          }

          if (v && (!point0 || !pointEqual(point0, point1))) {
            stream.point(point1[0], point1[1]);
          }

          point0 = point1, v0 = v, c0 = c;
        },
        lineEnd: function lineEnd() {
          if (v0) stream.lineEnd();
          point0 = null;
        },
        // Rejoin first and last segments if there were intersections and the first
        // and last points were visible.
        clean: function clean() {
          return _clean | (v00 && v0) << 1;
        }
      };
    } // Intersects the great circle between a and b with the clip circle.


    function intersect(a, b, two) {
      var pa = cartesian(a),
          pb = cartesian(b); // We have two planes, n1.p = d1 and n2.p = d2.
      // Find intersection line p(t) = c1 n1 + c2 n2 + t (n1 вЁЇ n2).

      var n1 = [1, 0, 0],
          // normal
      n2 = cartesianCross(pa, pb),
          n2n2 = cartesianDot(n2, n2),
          n1n2 = n2[0],
          // cartesianDot(n1, n2),
      determinant = n2n2 - n1n2 * n1n2; // Two polar points.

      if (!determinant) return !two && a;
      var c1 = cr * n2n2 / determinant,
          c2 = -cr * n1n2 / determinant,
          n1xn2 = cartesianCross(n1, n2),
          A = cartesianScale(n1, c1),
          B = cartesianScale(n2, c2);
      cartesianAddInPlace(A, B); // Solve |p(t)|^2 = 1.

      var u = n1xn2,
          w = cartesianDot(A, u),
          uu = cartesianDot(u, u),
          t2 = w * w - uu * (cartesianDot(A, A) - 1);
      if (t2 < 0) return;
      var t = sqrt(t2),
          q = cartesianScale(u, (-w - t) / uu);
      cartesianAddInPlace(q, A);
      q = spherical(q);
      if (!two) return q; // Two intersection points.

      var lambda0 = a[0],
          lambda1 = b[0],
          phi0 = a[1],
          phi1 = b[1],
          z;
      if (lambda1 < lambda0) z = lambda0, lambda0 = lambda1, lambda1 = z;
      var delta = lambda1 - lambda0,
          polar = abs(delta - pi$3) < epsilon$2,
          meridian = polar || delta < epsilon$2;
      if (!polar && phi1 < phi0) z = phi0, phi0 = phi1, phi1 = z; // Check that the first point is between a and b.

      if (meridian ? polar ? phi0 + phi1 > 0 ^ q[1] < (abs(q[0] - lambda0) < epsilon$2 ? phi0 : phi1) : phi0 <= q[1] && q[1] <= phi1 : delta > pi$3 ^ (lambda0 <= q[0] && q[0] <= lambda1)) {
        var q1 = cartesianScale(u, (-w + t) / uu);
        cartesianAddInPlace(q1, A);
        return [q, spherical(q1)];
      }
    } // Generates a 4-bit vector representing the location of a point relative to
    // the small circle's bounding box.


    function code(lambda, phi) {
      var r = smallRadius ? radius : pi$3 - radius,
          code = 0;
      if (lambda < -r) code |= 1; // left
      else if (lambda > r) code |= 2; // right

      if (phi < -r) code |= 4; // below
      else if (phi > r) code |= 8; // above

      return code;
    }

    return clip(visible, clipLine, interpolate, smallRadius ? [0, -radius] : [-pi$3, radius - pi$3]);
  }

  function clipLine (a, b, x0, y0, x1, y1) {
    var ax = a[0],
        ay = a[1],
        bx = b[0],
        by = b[1],
        t0 = 0,
        t1 = 1,
        dx = bx - ax,
        dy = by - ay,
        r;
    r = x0 - ax;
    if (!dx && r > 0) return;
    r /= dx;

    if (dx < 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    } else if (dx > 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    }

    r = x1 - ax;
    if (!dx && r < 0) return;
    r /= dx;

    if (dx < 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    } else if (dx > 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    }

    r = y0 - ay;
    if (!dy && r > 0) return;
    r /= dy;

    if (dy < 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    } else if (dy > 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    }

    r = y1 - ay;
    if (!dy && r < 0) return;
    r /= dy;

    if (dy < 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    } else if (dy > 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    }

    if (t0 > 0) a[0] = ax + t0 * dx, a[1] = ay + t0 * dy;
    if (t1 < 1) b[0] = ax + t1 * dx, b[1] = ay + t1 * dy;
    return true;
  }

  var clipMax = 1e9,
      clipMin = -clipMax; // TODO Use d3-polygonвЂ™s polygonContains here for the ring check?
  // TODO Eliminate duplicate buffering in clipBuffer and polygon.push?

  function clipRectangle(x0, y0, x1, y1) {
    function visible(x, y) {
      return x0 <= x && x <= x1 && y0 <= y && y <= y1;
    }

    function interpolate(from, to, direction, stream) {
      var a = 0,
          a1 = 0;

      if (from == null || (a = corner(from, direction)) !== (a1 = corner(to, direction)) || comparePoint(from, to) < 0 ^ direction > 0) {
        do {
          stream.point(a === 0 || a === 3 ? x0 : x1, a > 1 ? y1 : y0);
        } while ((a = (a + direction + 4) % 4) !== a1);
      } else {
        stream.point(to[0], to[1]);
      }
    }

    function corner(p, direction) {
      return abs(p[0] - x0) < epsilon$2 ? direction > 0 ? 0 : 3 : abs(p[0] - x1) < epsilon$2 ? direction > 0 ? 2 : 1 : abs(p[1] - y0) < epsilon$2 ? direction > 0 ? 1 : 0 : direction > 0 ? 3 : 2; // abs(p[1] - y1) < epsilon
    }

    function compareIntersection(a, b) {
      return comparePoint(a.x, b.x);
    }

    function comparePoint(a, b) {
      var ca = corner(a, 1),
          cb = corner(b, 1);
      return ca !== cb ? ca - cb : ca === 0 ? b[1] - a[1] : ca === 1 ? a[0] - b[0] : ca === 2 ? a[1] - b[1] : b[0] - a[0];
    }

    return function (stream) {
      var activeStream = stream,
          bufferStream = clipBuffer(),
          segments,
          polygon,
          ring,
          x__,
          y__,
          v__,
          // first point
      x_,
          y_,
          v_,
          // previous point
      first,
          clean;
      var clipStream = {
        point: point,
        lineStart: lineStart,
        lineEnd: lineEnd,
        polygonStart: polygonStart,
        polygonEnd: polygonEnd
      };

      function point(x, y) {
        if (visible(x, y)) activeStream.point(x, y);
      }

      function polygonInside() {
        var winding = 0;

        for (var i = 0, n = polygon.length; i < n; ++i) {
          for (var ring = polygon[i], j = 1, m = ring.length, point = ring[0], a0, a1, b0 = point[0], b1 = point[1]; j < m; ++j) {
            a0 = b0, a1 = b1, point = ring[j], b0 = point[0], b1 = point[1];

            if (a1 <= y1) {
              if (b1 > y1 && (b0 - a0) * (y1 - a1) > (b1 - a1) * (x0 - a0)) ++winding;
            } else {
              if (b1 <= y1 && (b0 - a0) * (y1 - a1) < (b1 - a1) * (x0 - a0)) --winding;
            }
          }
        }

        return winding;
      } // Buffer geometry within a polygon and then clip it en masse.


      function polygonStart() {
        activeStream = bufferStream, segments = [], polygon = [], clean = true;
      }

      function polygonEnd() {
        var startInside = polygonInside(),
            cleanInside = clean && startInside,
            visible = (segments = merge(segments)).length;

        if (cleanInside || visible) {
          stream.polygonStart();

          if (cleanInside) {
            stream.lineStart();
            interpolate(null, null, 1, stream);
            stream.lineEnd();
          }

          if (visible) {
            clipRejoin(segments, compareIntersection, startInside, interpolate, stream);
          }

          stream.polygonEnd();
        }

        activeStream = stream, segments = polygon = ring = null;
      }

      function lineStart() {
        clipStream.point = linePoint;
        if (polygon) polygon.push(ring = []);
        first = true;
        v_ = false;
        x_ = y_ = NaN;
      } // TODO rather than special-case polygons, simply handle them separately.
      // Ideally, coincident intersection points should be jittered to avoid
      // clipping issues.


      function lineEnd() {
        if (segments) {
          linePoint(x__, y__);
          if (v__ && v_) bufferStream.rejoin();
          segments.push(bufferStream.result());
        }

        clipStream.point = point;
        if (v_) activeStream.lineEnd();
      }

      function linePoint(x, y) {
        var v = visible(x, y);
        if (polygon) ring.push([x, y]);

        if (first) {
          x__ = x, y__ = y, v__ = v;
          first = false;

          if (v) {
            activeStream.lineStart();
            activeStream.point(x, y);
          }
        } else {
          if (v && v_) activeStream.point(x, y);else {
            var a = [x_ = Math.max(clipMin, Math.min(clipMax, x_)), y_ = Math.max(clipMin, Math.min(clipMax, y_))],
                b = [x = Math.max(clipMin, Math.min(clipMax, x)), y = Math.max(clipMin, Math.min(clipMax, y))];

            if (clipLine(a, b, x0, y0, x1, y1)) {
              if (!v_) {
                activeStream.lineStart();
                activeStream.point(a[0], a[1]);
              }

              activeStream.point(b[0], b[1]);
              if (!v) activeStream.lineEnd();
              clean = false;
            } else if (v) {
              activeStream.lineStart();
              activeStream.point(x, y);
              clean = false;
            }
          }
        }

        x_ = x, y_ = y, v_ = v;
      }

      return clipStream;
    };
  }

  function extent$1 () {
    var x0 = 0,
        y0 = 0,
        x1 = 960,
        y1 = 500,
        cache,
        cacheStream,
        clip;
    return clip = {
      stream: function stream(_stream) {
        return cache && cacheStream === _stream ? cache : cache = clipRectangle(x0, y0, x1, y1)(cacheStream = _stream);
      },
      extent: function extent(_) {
        return arguments.length ? (x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1], cache = cacheStream = null, clip) : [[x0, y0], [x1, y1]];
      }
    };
  }

  var lengthSum = adder(),
      lambda0$2,
      sinPhi0$1,
      cosPhi0$1;
  var lengthStream = {
    sphere: noop$2,
    point: noop$2,
    lineStart: lengthLineStart,
    lineEnd: noop$2,
    polygonStart: noop$2,
    polygonEnd: noop$2
  };

  function lengthLineStart() {
    lengthStream.point = lengthPointFirst;
    lengthStream.lineEnd = lengthLineEnd;
  }

  function lengthLineEnd() {
    lengthStream.point = lengthStream.lineEnd = noop$2;
  }

  function lengthPointFirst(lambda, phi) {
    lambda *= radians, phi *= radians;
    lambda0$2 = lambda, sinPhi0$1 = sin$1(phi), cosPhi0$1 = cos$1(phi);
    lengthStream.point = lengthPoint;
  }

  function lengthPoint(lambda, phi) {
    lambda *= radians, phi *= radians;
    var sinPhi = sin$1(phi),
        cosPhi = cos$1(phi),
        delta = abs(lambda - lambda0$2),
        cosDelta = cos$1(delta),
        sinDelta = sin$1(delta),
        x = cosPhi * sinDelta,
        y = cosPhi0$1 * sinPhi - sinPhi0$1 * cosPhi * cosDelta,
        z = sinPhi0$1 * sinPhi + cosPhi0$1 * cosPhi * cosDelta;
    lengthSum.add(atan2(sqrt(x * x + y * y), z));
    lambda0$2 = lambda, sinPhi0$1 = sinPhi, cosPhi0$1 = cosPhi;
  }

  function length$1 (object) {
    lengthSum.reset();
    geoStream(object, lengthStream);
    return +lengthSum;
  }

  var coordinates = [null, null],
      object$1 = {
    type: "LineString",
    coordinates: coordinates
  };
  function distance (a, b) {
    coordinates[0] = a;
    coordinates[1] = b;
    return length$1(object$1);
  }

  var containsObjectType = {
    Feature: function Feature(object, point) {
      return containsGeometry(object.geometry, point);
    },
    FeatureCollection: function FeatureCollection(object, point) {
      var features = object.features,
          i = -1,
          n = features.length;

      while (++i < n) {
        if (containsGeometry(features[i].geometry, point)) return true;
      }

      return false;
    }
  };
  var containsGeometryType = {
    Sphere: function Sphere() {
      return true;
    },
    Point: function Point(object, point) {
      return containsPoint(object.coordinates, point);
    },
    MultiPoint: function MultiPoint(object, point) {
      var coordinates = object.coordinates,
          i = -1,
          n = coordinates.length;

      while (++i < n) {
        if (containsPoint(coordinates[i], point)) return true;
      }

      return false;
    },
    LineString: function LineString(object, point) {
      return containsLine(object.coordinates, point);
    },
    MultiLineString: function MultiLineString(object, point) {
      var coordinates = object.coordinates,
          i = -1,
          n = coordinates.length;

      while (++i < n) {
        if (containsLine(coordinates[i], point)) return true;
      }

      return false;
    },
    Polygon: function Polygon(object, point) {
      return containsPolygon(object.coordinates, point);
    },
    MultiPolygon: function MultiPolygon(object, point) {
      var coordinates = object.coordinates,
          i = -1,
          n = coordinates.length;

      while (++i < n) {
        if (containsPolygon(coordinates[i], point)) return true;
      }

      return false;
    },
    GeometryCollection: function GeometryCollection(object, point) {
      var geometries = object.geometries,
          i = -1,
          n = geometries.length;

      while (++i < n) {
        if (containsGeometry(geometries[i], point)) return true;
      }

      return false;
    }
  };

  function containsGeometry(geometry, point) {
    return geometry && containsGeometryType.hasOwnProperty(geometry.type) ? containsGeometryType[geometry.type](geometry, point) : false;
  }

  function containsPoint(coordinates, point) {
    return distance(coordinates, point) === 0;
  }

  function containsLine(coordinates, point) {
    var ab = distance(coordinates[0], coordinates[1]),
        ao = distance(coordinates[0], point),
        ob = distance(point, coordinates[1]);
    return ao + ob <= ab + epsilon$2;
  }

  function containsPolygon(coordinates, point) {
    return !!polygonContains(coordinates.map(ringRadians), pointRadians(point));
  }

  function ringRadians(ring) {
    return ring = ring.map(pointRadians), ring.pop(), ring;
  }

  function pointRadians(point) {
    return [point[0] * radians, point[1] * radians];
  }

  function contains$1 (object, point) {
    return (object && containsObjectType.hasOwnProperty(object.type) ? containsObjectType[object.type] : containsGeometry)(object, point);
  }

  function graticuleX(y0, y1, dy) {
    var y = sequence(y0, y1 - epsilon$2, dy).concat(y1);
    return function (x) {
      return y.map(function (y) {
        return [x, y];
      });
    };
  }

  function graticuleY(x0, x1, dx) {
    var x = sequence(x0, x1 - epsilon$2, dx).concat(x1);
    return function (y) {
      return x.map(function (x) {
        return [x, y];
      });
    };
  }

  function graticule() {
    var x1,
        x0,
        X1,
        X0,
        y1,
        y0,
        Y1,
        Y0,
        dx = 10,
        dy = dx,
        DX = 90,
        DY = 360,
        x,
        y,
        X,
        Y,
        precision = 2.5;

    function graticule() {
      return {
        type: "MultiLineString",
        coordinates: lines()
      };
    }

    function lines() {
      return sequence(ceil(X0 / DX) * DX, X1, DX).map(X).concat(sequence(ceil(Y0 / DY) * DY, Y1, DY).map(Y)).concat(sequence(ceil(x0 / dx) * dx, x1, dx).filter(function (x) {
        return abs(x % DX) > epsilon$2;
      }).map(x)).concat(sequence(ceil(y0 / dy) * dy, y1, dy).filter(function (y) {
        return abs(y % DY) > epsilon$2;
      }).map(y));
    }

    graticule.lines = function () {
      return lines().map(function (coordinates) {
        return {
          type: "LineString",
          coordinates: coordinates
        };
      });
    };

    graticule.outline = function () {
      return {
        type: "Polygon",
        coordinates: [X(X0).concat(Y(Y1).slice(1), X(X1).reverse().slice(1), Y(Y0).reverse().slice(1))]
      };
    };

    graticule.extent = function (_) {
      if (!arguments.length) return graticule.extentMinor();
      return graticule.extentMajor(_).extentMinor(_);
    };

    graticule.extentMajor = function (_) {
      if (!arguments.length) return [[X0, Y0], [X1, Y1]];
      X0 = +_[0][0], X1 = +_[1][0];
      Y0 = +_[0][1], Y1 = +_[1][1];
      if (X0 > X1) _ = X0, X0 = X1, X1 = _;
      if (Y0 > Y1) _ = Y0, Y0 = Y1, Y1 = _;
      return graticule.precision(precision);
    };

    graticule.extentMinor = function (_) {
      if (!arguments.length) return [[x0, y0], [x1, y1]];
      x0 = +_[0][0], x1 = +_[1][0];
      y0 = +_[0][1], y1 = +_[1][1];
      if (x0 > x1) _ = x0, x0 = x1, x1 = _;
      if (y0 > y1) _ = y0, y0 = y1, y1 = _;
      return graticule.precision(precision);
    };

    graticule.step = function (_) {
      if (!arguments.length) return graticule.stepMinor();
      return graticule.stepMajor(_).stepMinor(_);
    };

    graticule.stepMajor = function (_) {
      if (!arguments.length) return [DX, DY];
      DX = +_[0], DY = +_[1];
      return graticule;
    };

    graticule.stepMinor = function (_) {
      if (!arguments.length) return [dx, dy];
      dx = +_[0], dy = +_[1];
      return graticule;
    };

    graticule.precision = function (_) {
      if (!arguments.length) return precision;
      precision = +_;
      x = graticuleX(y0, y1, 90);
      y = graticuleY(x0, x1, precision);
      X = graticuleX(Y0, Y1, 90);
      Y = graticuleY(X0, X1, precision);
      return graticule;
    };

    return graticule.extentMajor([[-180, -90 + epsilon$2], [180, 90 - epsilon$2]]).extentMinor([[-180, -80 - epsilon$2], [180, 80 + epsilon$2]]);
  }
  function graticule10() {
    return graticule()();
  }

  function interpolate$1 (a, b) {
    var x0 = a[0] * radians,
        y0 = a[1] * radians,
        x1 = b[0] * radians,
        y1 = b[1] * radians,
        cy0 = cos$1(y0),
        sy0 = sin$1(y0),
        cy1 = cos$1(y1),
        sy1 = sin$1(y1),
        kx0 = cy0 * cos$1(x0),
        ky0 = cy0 * sin$1(x0),
        kx1 = cy1 * cos$1(x1),
        ky1 = cy1 * sin$1(x1),
        d = 2 * asin(sqrt(haversin(y1 - y0) + cy0 * cy1 * haversin(x1 - x0))),
        k = sin$1(d);
    var interpolate = d ? function (t) {
      var B = sin$1(t *= d) / k,
          A = sin$1(d - t) / k,
          x = A * kx0 + B * kx1,
          y = A * ky0 + B * ky1,
          z = A * sy0 + B * sy1;
      return [atan2(y, x) * degrees$1, atan2(z, sqrt(x * x + y * y)) * degrees$1];
    } : function () {
      return [x0 * degrees$1, y0 * degrees$1];
    };
    interpolate.distance = d;
    return interpolate;
  }

  function identity$4 (x) {
    return x;
  }

  var areaSum$1 = adder(),
      areaRingSum$1 = adder(),
      x00,
      y00,
      x0$1,
      y0$1;
  var areaStream$1 = {
    point: noop$2,
    lineStart: noop$2,
    lineEnd: noop$2,
    polygonStart: function polygonStart() {
      areaStream$1.lineStart = areaRingStart$1;
      areaStream$1.lineEnd = areaRingEnd$1;
    },
    polygonEnd: function polygonEnd() {
      areaStream$1.lineStart = areaStream$1.lineEnd = areaStream$1.point = noop$2;
      areaSum$1.add(abs(areaRingSum$1));
      areaRingSum$1.reset();
    },
    result: function result() {
      var area = areaSum$1 / 2;
      areaSum$1.reset();
      return area;
    }
  };

  function areaRingStart$1() {
    areaStream$1.point = areaPointFirst$1;
  }

  function areaPointFirst$1(x, y) {
    areaStream$1.point = areaPoint$1;
    x00 = x0$1 = x, y00 = y0$1 = y;
  }

  function areaPoint$1(x, y) {
    areaRingSum$1.add(y0$1 * x - x0$1 * y);
    x0$1 = x, y0$1 = y;
  }

  function areaRingEnd$1() {
    areaPoint$1(x00, y00);
  }

  var x0$2 = Infinity,
      y0$2 = x0$2,
      x1 = -x0$2,
      y1 = x1;
  var boundsStream$1 = {
    point: boundsPoint$1,
    lineStart: noop$2,
    lineEnd: noop$2,
    polygonStart: noop$2,
    polygonEnd: noop$2,
    result: function result() {
      var bounds = [[x0$2, y0$2], [x1, y1]];
      x1 = y1 = -(y0$2 = x0$2 = Infinity);
      return bounds;
    }
  };

  function boundsPoint$1(x, y) {
    if (x < x0$2) x0$2 = x;
    if (x > x1) x1 = x;
    if (y < y0$2) y0$2 = y;
    if (y > y1) y1 = y;
  }

  var X0$1 = 0,
      Y0$1 = 0,
      Z0$1 = 0,
      X1$1 = 0,
      Y1$1 = 0,
      Z1$1 = 0,
      X2$1 = 0,
      Y2$1 = 0,
      Z2$1 = 0,
      x00$1,
      y00$1,
      x0$3,
      y0$3;
  var centroidStream$1 = {
    point: centroidPoint$1,
    lineStart: centroidLineStart$1,
    lineEnd: centroidLineEnd$1,
    polygonStart: function polygonStart() {
      centroidStream$1.lineStart = centroidRingStart$1;
      centroidStream$1.lineEnd = centroidRingEnd$1;
    },
    polygonEnd: function polygonEnd() {
      centroidStream$1.point = centroidPoint$1;
      centroidStream$1.lineStart = centroidLineStart$1;
      centroidStream$1.lineEnd = centroidLineEnd$1;
    },
    result: function result() {
      var centroid = Z2$1 ? [X2$1 / Z2$1, Y2$1 / Z2$1] : Z1$1 ? [X1$1 / Z1$1, Y1$1 / Z1$1] : Z0$1 ? [X0$1 / Z0$1, Y0$1 / Z0$1] : [NaN, NaN];
      X0$1 = Y0$1 = Z0$1 = X1$1 = Y1$1 = Z1$1 = X2$1 = Y2$1 = Z2$1 = 0;
      return centroid;
    }
  };

  function centroidPoint$1(x, y) {
    X0$1 += x;
    Y0$1 += y;
    ++Z0$1;
  }

  function centroidLineStart$1() {
    centroidStream$1.point = centroidPointFirstLine;
  }

  function centroidPointFirstLine(x, y) {
    centroidStream$1.point = centroidPointLine;
    centroidPoint$1(x0$3 = x, y0$3 = y);
  }

  function centroidPointLine(x, y) {
    var dx = x - x0$3,
        dy = y - y0$3,
        z = sqrt(dx * dx + dy * dy);
    X1$1 += z * (x0$3 + x) / 2;
    Y1$1 += z * (y0$3 + y) / 2;
    Z1$1 += z;
    centroidPoint$1(x0$3 = x, y0$3 = y);
  }

  function centroidLineEnd$1() {
    centroidStream$1.point = centroidPoint$1;
  }

  function centroidRingStart$1() {
    centroidStream$1.point = centroidPointFirstRing;
  }

  function centroidRingEnd$1() {
    centroidPointRing(x00$1, y00$1);
  }

  function centroidPointFirstRing(x, y) {
    centroidStream$1.point = centroidPointRing;
    centroidPoint$1(x00$1 = x0$3 = x, y00$1 = y0$3 = y);
  }

  function centroidPointRing(x, y) {
    var dx = x - x0$3,
        dy = y - y0$3,
        z = sqrt(dx * dx + dy * dy);
    X1$1 += z * (x0$3 + x) / 2;
    Y1$1 += z * (y0$3 + y) / 2;
    Z1$1 += z;
    z = y0$3 * x - x0$3 * y;
    X2$1 += z * (x0$3 + x);
    Y2$1 += z * (y0$3 + y);
    Z2$1 += z * 3;
    centroidPoint$1(x0$3 = x, y0$3 = y);
  }

  function PathContext(context) {
    this._context = context;
  }
  PathContext.prototype = {
    _radius: 4.5,
    pointRadius: function pointRadius(_) {
      return this._radius = _, this;
    },
    polygonStart: function polygonStart() {
      this._line = 0;
    },
    polygonEnd: function polygonEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._line === 0) this._context.closePath();
      this._point = NaN;
    },
    point: function point(x, y) {
      switch (this._point) {
        case 0:
          {
            this._context.moveTo(x, y);

            this._point = 1;
            break;
          }

        case 1:
          {
            this._context.lineTo(x, y);

            break;
          }

        default:
          {
            this._context.moveTo(x + this._radius, y);

            this._context.arc(x, y, this._radius, 0, tau$3);

            break;
          }
      }
    },
    result: noop$2
  };

  var lengthSum$1 = adder(),
      lengthRing,
      x00$2,
      y00$2,
      x0$4,
      y0$4;
  var lengthStream$1 = {
    point: noop$2,
    lineStart: function lineStart() {
      lengthStream$1.point = lengthPointFirst$1;
    },
    lineEnd: function lineEnd() {
      if (lengthRing) lengthPoint$1(x00$2, y00$2);
      lengthStream$1.point = noop$2;
    },
    polygonStart: function polygonStart() {
      lengthRing = true;
    },
    polygonEnd: function polygonEnd() {
      lengthRing = null;
    },
    result: function result() {
      var length = +lengthSum$1;
      lengthSum$1.reset();
      return length;
    }
  };

  function lengthPointFirst$1(x, y) {
    lengthStream$1.point = lengthPoint$1;
    x00$2 = x0$4 = x, y00$2 = y0$4 = y;
  }

  function lengthPoint$1(x, y) {
    x0$4 -= x, y0$4 -= y;
    lengthSum$1.add(sqrt(x0$4 * x0$4 + y0$4 * y0$4));
    x0$4 = x, y0$4 = y;
  }

  function PathString() {
    this._string = [];
  }
  PathString.prototype = {
    _radius: 4.5,
    _circle: circle$1(4.5),
    pointRadius: function pointRadius(_) {
      if ((_ = +_) !== this._radius) this._radius = _, this._circle = null;
      return this;
    },
    polygonStart: function polygonStart() {
      this._line = 0;
    },
    polygonEnd: function polygonEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._line === 0) this._string.push("Z");
      this._point = NaN;
    },
    point: function point(x, y) {
      switch (this._point) {
        case 0:
          {
            this._string.push("M", x, ",", y);

            this._point = 1;
            break;
          }

        case 1:
          {
            this._string.push("L", x, ",", y);

            break;
          }

        default:
          {
            if (this._circle == null) this._circle = circle$1(this._radius);

            this._string.push("M", x, ",", y, this._circle);

            break;
          }
      }
    },
    result: function result() {
      if (this._string.length) {
        var result = this._string.join("");

        this._string = [];
        return result;
      } else {
        return null;
      }
    }
  };

  function circle$1(radius) {
    return "m0," + radius + "a" + radius + "," + radius + " 0 1,1 0," + -2 * radius + "a" + radius + "," + radius + " 0 1,1 0," + 2 * radius + "z";
  }

  function index$1 (projection, context) {
    var pointRadius = 4.5,
        projectionStream,
        contextStream;

    function path(object) {
      if (object) {
        if (typeof pointRadius === "function") contextStream.pointRadius(+pointRadius.apply(this, arguments));
        geoStream(object, projectionStream(contextStream));
      }

      return contextStream.result();
    }

    path.area = function (object) {
      geoStream(object, projectionStream(areaStream$1));
      return areaStream$1.result();
    };

    path.measure = function (object) {
      geoStream(object, projectionStream(lengthStream$1));
      return lengthStream$1.result();
    };

    path.bounds = function (object) {
      geoStream(object, projectionStream(boundsStream$1));
      return boundsStream$1.result();
    };

    path.centroid = function (object) {
      geoStream(object, projectionStream(centroidStream$1));
      return centroidStream$1.result();
    };

    path.projection = function (_) {
      return arguments.length ? (projectionStream = _ == null ? (projection = null, identity$4) : (projection = _).stream, path) : projection;
    };

    path.context = function (_) {
      if (!arguments.length) return context;
      contextStream = _ == null ? (context = null, new PathString()) : new PathContext(context = _);
      if (typeof pointRadius !== "function") contextStream.pointRadius(pointRadius);
      return path;
    };

    path.pointRadius = function (_) {
      if (!arguments.length) return pointRadius;
      pointRadius = typeof _ === "function" ? _ : (contextStream.pointRadius(+_), +_);
      return path;
    };

    return path.projection(projection).context(context);
  }

  function transform (methods) {
    return {
      stream: transformer(methods)
    };
  }
  function transformer(methods) {
    return function (stream) {
      var s = new TransformStream();

      for (var key in methods) {
        s[key] = methods[key];
      }

      s.stream = stream;
      return s;
    };
  }

  function TransformStream() {}

  TransformStream.prototype = {
    constructor: TransformStream,
    point: function point(x, y) {
      this.stream.point(x, y);
    },
    sphere: function sphere() {
      this.stream.sphere();
    },
    lineStart: function lineStart() {
      this.stream.lineStart();
    },
    lineEnd: function lineEnd() {
      this.stream.lineEnd();
    },
    polygonStart: function polygonStart() {
      this.stream.polygonStart();
    },
    polygonEnd: function polygonEnd() {
      this.stream.polygonEnd();
    }
  };

  function fit(projection, fitBounds, object) {
    var clip = projection.clipExtent && projection.clipExtent();
    projection.scale(150).translate([0, 0]);
    if (clip != null) projection.clipExtent(null);
    geoStream(object, projection.stream(boundsStream$1));
    fitBounds(boundsStream$1.result());
    if (clip != null) projection.clipExtent(clip);
    return projection;
  }

  function fitExtent(projection, extent, object) {
    return fit(projection, function (b) {
      var w = extent[1][0] - extent[0][0],
          h = extent[1][1] - extent[0][1],
          k = Math.min(w / (b[1][0] - b[0][0]), h / (b[1][1] - b[0][1])),
          x = +extent[0][0] + (w - k * (b[1][0] + b[0][0])) / 2,
          y = +extent[0][1] + (h - k * (b[1][1] + b[0][1])) / 2;
      projection.scale(150 * k).translate([x, y]);
    }, object);
  }
  function fitSize(projection, size, object) {
    return fitExtent(projection, [[0, 0], size], object);
  }
  function fitWidth(projection, width, object) {
    return fit(projection, function (b) {
      var w = +width,
          k = w / (b[1][0] - b[0][0]),
          x = (w - k * (b[1][0] + b[0][0])) / 2,
          y = -k * b[0][1];
      projection.scale(150 * k).translate([x, y]);
    }, object);
  }
  function fitHeight(projection, height, object) {
    return fit(projection, function (b) {
      var h = +height,
          k = h / (b[1][1] - b[0][1]),
          x = -k * b[0][0],
          y = (h - k * (b[1][1] + b[0][1])) / 2;
      projection.scale(150 * k).translate([x, y]);
    }, object);
  }

  var maxDepth = 16,
      // maximum depth of subdivision
  cosMinDistance = cos$1(30 * radians); // cos(minimum angular distance)

  function resample (project, delta2) {
    return +delta2 ? resample$1(project, delta2) : resampleNone(project);
  }

  function resampleNone(project) {
    return transformer({
      point: function point(x, y) {
        x = project(x, y);
        this.stream.point(x[0], x[1]);
      }
    });
  }

  function resample$1(project, delta2) {
    function resampleLineTo(x0, y0, lambda0, a0, b0, c0, x1, y1, lambda1, a1, b1, c1, depth, stream) {
      var dx = x1 - x0,
          dy = y1 - y0,
          d2 = dx * dx + dy * dy;

      if (d2 > 4 * delta2 && depth--) {
        var a = a0 + a1,
            b = b0 + b1,
            c = c0 + c1,
            m = sqrt(a * a + b * b + c * c),
            phi2 = asin(c /= m),
            lambda2 = abs(abs(c) - 1) < epsilon$2 || abs(lambda0 - lambda1) < epsilon$2 ? (lambda0 + lambda1) / 2 : atan2(b, a),
            p = project(lambda2, phi2),
            x2 = p[0],
            y2 = p[1],
            dx2 = x2 - x0,
            dy2 = y2 - y0,
            dz = dy * dx2 - dx * dy2;

        if (dz * dz / d2 > delta2 // perpendicular projected distance
        || abs((dx * dx2 + dy * dy2) / d2 - 0.5) > 0.3 // midpoint close to an end
        || a0 * a1 + b0 * b1 + c0 * c1 < cosMinDistance) {
          // angular distance
          resampleLineTo(x0, y0, lambda0, a0, b0, c0, x2, y2, lambda2, a /= m, b /= m, c, depth, stream);
          stream.point(x2, y2);
          resampleLineTo(x2, y2, lambda2, a, b, c, x1, y1, lambda1, a1, b1, c1, depth, stream);
        }
      }
    }

    return function (stream) {
      var lambda00, x00, y00, a00, b00, c00, // first point
      lambda0, x0, y0, a0, b0, c0; // previous point

      var resampleStream = {
        point: point,
        lineStart: lineStart,
        lineEnd: lineEnd,
        polygonStart: function polygonStart() {
          stream.polygonStart();
          resampleStream.lineStart = ringStart;
        },
        polygonEnd: function polygonEnd() {
          stream.polygonEnd();
          resampleStream.lineStart = lineStart;
        }
      };

      function point(x, y) {
        x = project(x, y);
        stream.point(x[0], x[1]);
      }

      function lineStart() {
        x0 = NaN;
        resampleStream.point = linePoint;
        stream.lineStart();
      }

      function linePoint(lambda, phi) {
        var c = cartesian([lambda, phi]),
            p = project(lambda, phi);
        resampleLineTo(x0, y0, lambda0, a0, b0, c0, x0 = p[0], y0 = p[1], lambda0 = lambda, a0 = c[0], b0 = c[1], c0 = c[2], maxDepth, stream);
        stream.point(x0, y0);
      }

      function lineEnd() {
        resampleStream.point = point;
        stream.lineEnd();
      }

      function ringStart() {
        lineStart();
        resampleStream.point = ringPoint;
        resampleStream.lineEnd = ringEnd;
      }

      function ringPoint(lambda, phi) {
        linePoint(lambda00 = lambda, phi), x00 = x0, y00 = y0, a00 = a0, b00 = b0, c00 = c0;
        resampleStream.point = linePoint;
      }

      function ringEnd() {
        resampleLineTo(x0, y0, lambda0, a0, b0, c0, x00, y00, lambda00, a00, b00, c00, maxDepth, stream);
        resampleStream.lineEnd = lineEnd;
        lineEnd();
      }

      return resampleStream;
    };
  }

  var transformRadians = transformer({
    point: function point(x, y) {
      this.stream.point(x * radians, y * radians);
    }
  });

  function transformRotate(rotate) {
    return transformer({
      point: function point(x, y) {
        var r = rotate(x, y);
        return this.stream.point(r[0], r[1]);
      }
    });
  }

  function scaleTranslate(k, dx, dy) {
    function transform$$1(x, y) {
      return [dx + k * x, dy - k * y];
    }

    transform$$1.invert = function (x, y) {
      return [(x - dx) / k, (dy - y) / k];
    };

    return transform$$1;
  }

  function scaleTranslateRotate(k, dx, dy, alpha) {
    var cosAlpha = cos$1(alpha),
        sinAlpha = sin$1(alpha),
        a = cosAlpha * k,
        b = sinAlpha * k,
        ai = cosAlpha / k,
        bi = sinAlpha / k,
        ci = (sinAlpha * dy - cosAlpha * dx) / k,
        fi = (sinAlpha * dx + cosAlpha * dy) / k;

    function transform$$1(x, y) {
      return [a * x - b * y + dx, dy - b * x - a * y];
    }

    transform$$1.invert = function (x, y) {
      return [ai * x - bi * y + ci, fi - bi * x - ai * y];
    };

    return transform$$1;
  }

  function projection(project) {
    return projectionMutator(function () {
      return project;
    })();
  }
  function projectionMutator(projectAt) {
    var project,
        k = 150,
        // scale
    x = 480,
        y = 250,
        // translate
    lambda = 0,
        phi = 0,
        // center
    deltaLambda = 0,
        deltaPhi = 0,
        deltaGamma = 0,
        rotate,
        // pre-rotate
    alpha = 0,
        // post-rotate
    theta = null,
        preclip = clipAntimeridian,
        // pre-clip angle
    x0 = null,
        y0,
        x1,
        y1,
        postclip = identity$4,
        // post-clip extent
    delta2 = 0.5,
        // precision
    projectResample,
        projectTransform,
        projectRotateTransform,
        cache,
        cacheStream;

    function projection(point) {
      return projectRotateTransform(point[0] * radians, point[1] * radians);
    }

    function invert(point) {
      point = projectRotateTransform.invert(point[0], point[1]);
      return point && [point[0] * degrees$1, point[1] * degrees$1];
    }

    projection.stream = function (stream) {
      return cache && cacheStream === stream ? cache : cache = transformRadians(transformRotate(rotate)(preclip(projectResample(postclip(cacheStream = stream)))));
    };

    projection.preclip = function (_) {
      return arguments.length ? (preclip = _, theta = undefined, reset()) : preclip;
    };

    projection.postclip = function (_) {
      return arguments.length ? (postclip = _, x0 = y0 = x1 = y1 = null, reset()) : postclip;
    };

    projection.clipAngle = function (_) {
      return arguments.length ? (preclip = +_ ? clipCircle(theta = _ * radians) : (theta = null, clipAntimeridian), reset()) : theta * degrees$1;
    };

    projection.clipExtent = function (_) {
      return arguments.length ? (postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity$4) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]];
    };

    projection.scale = function (_) {
      return arguments.length ? (k = +_, recenter()) : k;
    };

    projection.translate = function (_) {
      return arguments.length ? (x = +_[0], y = +_[1], recenter()) : [x, y];
    };

    projection.center = function (_) {
      return arguments.length ? (lambda = _[0] % 360 * radians, phi = _[1] % 360 * radians, recenter()) : [lambda * degrees$1, phi * degrees$1];
    };

    projection.rotate = function (_) {
      return arguments.length ? (deltaLambda = _[0] % 360 * radians, deltaPhi = _[1] % 360 * radians, deltaGamma = _.length > 2 ? _[2] % 360 * radians : 0, recenter()) : [deltaLambda * degrees$1, deltaPhi * degrees$1, deltaGamma * degrees$1];
    };

    projection.angle = function (_) {
      return arguments.length ? (alpha = _ % 360 * radians, recenter()) : alpha * degrees$1;
    };

    projection.precision = function (_) {
      return arguments.length ? (projectResample = resample(projectTransform, delta2 = _ * _), reset()) : sqrt(delta2);
    };

    projection.fitExtent = function (extent, object) {
      return fitExtent(projection, extent, object);
    };

    projection.fitSize = function (size, object) {
      return fitSize(projection, size, object);
    };

    projection.fitWidth = function (width, object) {
      return fitWidth(projection, width, object);
    };

    projection.fitHeight = function (height, object) {
      return fitHeight(projection, height, object);
    };

    function recenter() {
      var center = scaleTranslateRotate(k, 0, 0, alpha).apply(null, project(lambda, phi)),
          transform$$1 = (alpha ? scaleTranslateRotate : scaleTranslate)(k, x - center[0], y - center[1], alpha);
      rotate = rotateRadians(deltaLambda, deltaPhi, deltaGamma);
      projectTransform = compose(project, transform$$1);
      projectRotateTransform = compose(rotate, projectTransform);
      projectResample = resample(projectTransform, delta2);
      return reset();
    }

    function reset() {
      cache = cacheStream = null;
      return projection;
    }

    return function () {
      project = projectAt.apply(this, arguments);
      projection.invert = project.invert && invert;
      return recenter();
    };
  }

  function conicProjection(projectAt) {
    var phi0 = 0,
        phi1 = pi$3 / 3,
        m = projectionMutator(projectAt),
        p = m(phi0, phi1);

    p.parallels = function (_) {
      return arguments.length ? m(phi0 = _[0] * radians, phi1 = _[1] * radians) : [phi0 * degrees$1, phi1 * degrees$1];
    };

    return p;
  }

  function cylindricalEqualAreaRaw(phi0) {
    var cosPhi0 = cos$1(phi0);

    function forward(lambda, phi) {
      return [lambda * cosPhi0, sin$1(phi) / cosPhi0];
    }

    forward.invert = function (x, y) {
      return [x / cosPhi0, asin(y * cosPhi0)];
    };

    return forward;
  }

  function conicEqualAreaRaw(y0, y1) {
    var sy0 = sin$1(y0),
        n = (sy0 + sin$1(y1)) / 2; // Are the parallels symmetrical around the Equator?

    if (abs(n) < epsilon$2) return cylindricalEqualAreaRaw(y0);
    var c = 1 + sy0 * (2 * n - sy0),
        r0 = sqrt(c) / n;

    function project(x, y) {
      var r = sqrt(c - 2 * n * sin$1(y)) / n;
      return [r * sin$1(x *= n), r0 - r * cos$1(x)];
    }

    project.invert = function (x, y) {
      var r0y = r0 - y;
      return [atan2(x, abs(r0y)) / n * sign(r0y), asin((c - (x * x + r0y * r0y) * n * n) / (2 * n))];
    };

    return project;
  }
  function conicEqualArea () {
    return conicProjection(conicEqualAreaRaw).scale(155.424).center([0, 33.6442]);
  }

  function albers () {
    return conicEqualArea().parallels([29.5, 45.5]).scale(1070).translate([480, 250]).rotate([96, 0]).center([-0.6, 38.7]);
  }

  // as this will avoid emitting interleaving lines and polygons.

  function multiplex(streams) {
    var n = streams.length;
    return {
      point: function point(x, y) {
        var i = -1;

        while (++i < n) {
          streams[i].point(x, y);
        }
      },
      sphere: function sphere() {
        var i = -1;

        while (++i < n) {
          streams[i].sphere();
        }
      },
      lineStart: function lineStart() {
        var i = -1;

        while (++i < n) {
          streams[i].lineStart();
        }
      },
      lineEnd: function lineEnd() {
        var i = -1;

        while (++i < n) {
          streams[i].lineEnd();
        }
      },
      polygonStart: function polygonStart() {
        var i = -1;

        while (++i < n) {
          streams[i].polygonStart();
        }
      },
      polygonEnd: function polygonEnd() {
        var i = -1;

        while (++i < n) {
          streams[i].polygonEnd();
        }
      }
    };
  } // A composite projection for the United States, configured by default for
  // 960Г—500. The projection also works quite well at 960Г—600 if you change the
  // scale to 1285 and adjust the translate accordingly. The set of standard
  // parallels for each region comes from USGS, which is published here:
  // http://egsc.usgs.gov/isb/pubs/MapProjections/projections.html#albers


  function albersUsa () {
    var cache,
        cacheStream,
        lower48 = albers(),
        lower48Point,
        alaska = conicEqualArea().rotate([154, 0]).center([-2, 58.5]).parallels([55, 65]),
        alaskaPoint,
        // EPSG:3338
    hawaii = conicEqualArea().rotate([157, 0]).center([-3, 19.9]).parallels([8, 18]),
        hawaiiPoint,
        // ESRI:102007
    _point,
        pointStream = {
      point: function point(x, y) {
        _point = [x, y];
      }
    };

    function albersUsa(coordinates) {
      var x = coordinates[0],
          y = coordinates[1];
      return _point = null, (lower48Point.point(x, y), _point) || (alaskaPoint.point(x, y), _point) || (hawaiiPoint.point(x, y), _point);
    }

    albersUsa.invert = function (coordinates) {
      var k = lower48.scale(),
          t = lower48.translate(),
          x = (coordinates[0] - t[0]) / k,
          y = (coordinates[1] - t[1]) / k;
      return (y >= 0.120 && y < 0.234 && x >= -0.425 && x < -0.214 ? alaska : y >= 0.166 && y < 0.234 && x >= -0.214 && x < -0.115 ? hawaii : lower48).invert(coordinates);
    };

    albersUsa.stream = function (stream) {
      return cache && cacheStream === stream ? cache : cache = multiplex([lower48.stream(cacheStream = stream), alaska.stream(stream), hawaii.stream(stream)]);
    };

    albersUsa.precision = function (_) {
      if (!arguments.length) return lower48.precision();
      lower48.precision(_), alaska.precision(_), hawaii.precision(_);
      return reset();
    };

    albersUsa.scale = function (_) {
      if (!arguments.length) return lower48.scale();
      lower48.scale(_), alaska.scale(_ * 0.35), hawaii.scale(_);
      return albersUsa.translate(lower48.translate());
    };

    albersUsa.translate = function (_) {
      if (!arguments.length) return lower48.translate();
      var k = lower48.scale(),
          x = +_[0],
          y = +_[1];
      lower48Point = lower48.translate(_).clipExtent([[x - 0.455 * k, y - 0.238 * k], [x + 0.455 * k, y + 0.238 * k]]).stream(pointStream);
      alaskaPoint = alaska.translate([x - 0.307 * k, y + 0.201 * k]).clipExtent([[x - 0.425 * k + epsilon$2, y + 0.120 * k + epsilon$2], [x - 0.214 * k - epsilon$2, y + 0.234 * k - epsilon$2]]).stream(pointStream);
      hawaiiPoint = hawaii.translate([x - 0.205 * k, y + 0.212 * k]).clipExtent([[x - 0.214 * k + epsilon$2, y + 0.166 * k + epsilon$2], [x - 0.115 * k - epsilon$2, y + 0.234 * k - epsilon$2]]).stream(pointStream);
      return reset();
    };

    albersUsa.fitExtent = function (extent, object) {
      return fitExtent(albersUsa, extent, object);
    };

    albersUsa.fitSize = function (size, object) {
      return fitSize(albersUsa, size, object);
    };

    albersUsa.fitWidth = function (width, object) {
      return fitWidth(albersUsa, width, object);
    };

    albersUsa.fitHeight = function (height, object) {
      return fitHeight(albersUsa, height, object);
    };

    function reset() {
      cache = cacheStream = null;
      return albersUsa;
    }

    return albersUsa.scale(1070);
  }

  function azimuthalRaw(scale) {
    return function (x, y) {
      var cx = cos$1(x),
          cy = cos$1(y),
          k = scale(cx * cy);
      return [k * cy * sin$1(x), k * sin$1(y)];
    };
  }
  function azimuthalInvert(angle) {
    return function (x, y) {
      var z = sqrt(x * x + y * y),
          c = angle(z),
          sc = sin$1(c),
          cc = cos$1(c);
      return [atan2(x * sc, z * cc), asin(z && y * sc / z)];
    };
  }

  var azimuthalEqualAreaRaw = azimuthalRaw(function (cxcy) {
    return sqrt(2 / (1 + cxcy));
  });
  azimuthalEqualAreaRaw.invert = azimuthalInvert(function (z) {
    return 2 * asin(z / 2);
  });
  function azimuthalEqualArea () {
    return projection(azimuthalEqualAreaRaw).scale(124.75).clipAngle(180 - 1e-3);
  }

  var azimuthalEquidistantRaw = azimuthalRaw(function (c) {
    return (c = acos(c)) && c / sin$1(c);
  });
  azimuthalEquidistantRaw.invert = azimuthalInvert(function (z) {
    return z;
  });
  function azimuthalEquidistant () {
    return projection(azimuthalEquidistantRaw).scale(79.4188).clipAngle(180 - 1e-3);
  }

  function mercatorRaw(lambda, phi) {
    return [lambda, log(tan((halfPi$2 + phi) / 2))];
  }

  mercatorRaw.invert = function (x, y) {
    return [x, 2 * atan(exp(y)) - halfPi$2];
  };

  function mercator () {
    return mercatorProjection(mercatorRaw).scale(961 / tau$3);
  }
  function mercatorProjection(project) {
    var m = projection(project),
        center = m.center,
        scale = m.scale,
        translate = m.translate,
        clipExtent = m.clipExtent,
        x0 = null,
        y0,
        x1,
        y1; // clip extent

    m.scale = function (_) {
      return arguments.length ? (scale(_), reclip()) : scale();
    };

    m.translate = function (_) {
      return arguments.length ? (translate(_), reclip()) : translate();
    };

    m.center = function (_) {
      return arguments.length ? (center(_), reclip()) : center();
    };

    m.clipExtent = function (_) {
      return arguments.length ? (_ == null ? x0 = y0 = x1 = y1 = null : (x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reclip()) : x0 == null ? null : [[x0, y0], [x1, y1]];
    };

    function reclip() {
      var k = pi$3 * scale(),
          t = m(rotation(m.rotate()).invert([0, 0]));
      return clipExtent(x0 == null ? [[t[0] - k, t[1] - k], [t[0] + k, t[1] + k]] : project === mercatorRaw ? [[Math.max(t[0] - k, x0), y0], [Math.min(t[0] + k, x1), y1]] : [[x0, Math.max(t[1] - k, y0)], [x1, Math.min(t[1] + k, y1)]]);
    }

    return reclip();
  }

  function tany(y) {
    return tan((halfPi$2 + y) / 2);
  }

  function conicConformalRaw(y0, y1) {
    var cy0 = cos$1(y0),
        n = y0 === y1 ? sin$1(y0) : log(cy0 / cos$1(y1)) / log(tany(y1) / tany(y0)),
        f = cy0 * pow(tany(y0), n) / n;
    if (!n) return mercatorRaw;

    function project(x, y) {
      if (f > 0) {
        if (y < -halfPi$2 + epsilon$2) y = -halfPi$2 + epsilon$2;
      } else {
        if (y > halfPi$2 - epsilon$2) y = halfPi$2 - epsilon$2;
      }

      var r = f / pow(tany(y), n);
      return [r * sin$1(n * x), f - r * cos$1(n * x)];
    }

    project.invert = function (x, y) {
      var fy = f - y,
          r = sign(n) * sqrt(x * x + fy * fy);
      return [atan2(x, abs(fy)) / n * sign(fy), 2 * atan(pow(f / r, 1 / n)) - halfPi$2];
    };

    return project;
  }
  function conicConformal () {
    return conicProjection(conicConformalRaw).scale(109.5).parallels([30, 30]);
  }

  function equirectangularRaw(lambda, phi) {
    return [lambda, phi];
  }
  equirectangularRaw.invert = equirectangularRaw;
  function equirectangular () {
    return projection(equirectangularRaw).scale(152.63);
  }

  function conicEquidistantRaw(y0, y1) {
    var cy0 = cos$1(y0),
        n = y0 === y1 ? sin$1(y0) : (cy0 - cos$1(y1)) / (y1 - y0),
        g = cy0 / n + y0;
    if (abs(n) < epsilon$2) return equirectangularRaw;

    function project(x, y) {
      var gy = g - y,
          nx = n * x;
      return [gy * sin$1(nx), g - gy * cos$1(nx)];
    }

    project.invert = function (x, y) {
      var gy = g - y;
      return [atan2(x, abs(gy)) / n * sign(gy), g - sign(n) * sqrt(x * x + gy * gy)];
    };

    return project;
  }
  function conicEquidistant () {
    return conicProjection(conicEquidistantRaw).scale(131.154).center([0, 13.9389]);
  }

  var A1 = 1.340264,
      A2 = -0.081106,
      A3 = 0.000893,
      A4 = 0.003796,
      M = sqrt(3) / 2,
      iterations = 12;
  function equalEarthRaw(lambda, phi) {
    var l = asin(M * sin$1(phi)),
        l2 = l * l,
        l6 = l2 * l2 * l2;
    return [lambda * cos$1(l) / (M * (A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2))), l * (A1 + A2 * l2 + l6 * (A3 + A4 * l2))];
  }

  equalEarthRaw.invert = function (x, y) {
    var l = y,
        l2 = l * l,
        l6 = l2 * l2 * l2;

    for (var i = 0, delta, fy, fpy; i < iterations; ++i) {
      fy = l * (A1 + A2 * l2 + l6 * (A3 + A4 * l2)) - y;
      fpy = A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2);
      l -= delta = fy / fpy, l2 = l * l, l6 = l2 * l2 * l2;
      if (abs(delta) < epsilon2$1) break;
    }

    return [M * x * (A1 + 3 * A2 * l2 + l6 * (7 * A3 + 9 * A4 * l2)) / cos$1(l), asin(sin$1(l) / M)];
  };

  function equalEarth () {
    return projection(equalEarthRaw).scale(177.158);
  }

  function gnomonicRaw(x, y) {
    var cy = cos$1(y),
        k = cos$1(x) * cy;
    return [cy * sin$1(x) / k, sin$1(y) / k];
  }
  gnomonicRaw.invert = azimuthalInvert(atan);
  function gnomonic () {
    return projection(gnomonicRaw).scale(144.049).clipAngle(60);
  }

  function scaleTranslate$1(kx, ky, tx, ty) {
    return kx === 1 && ky === 1 && tx === 0 && ty === 0 ? identity$4 : transformer({
      point: function point(x, y) {
        this.stream.point(x * kx + tx, y * ky + ty);
      }
    });
  }

  function identity$5 () {
    var k = 1,
        tx = 0,
        ty = 0,
        sx = 1,
        sy = 1,
        transform$$1 = identity$4,
        // scale, translate and reflect
    x0 = null,
        y0,
        x1,
        y1,
        // clip extent
    _postclip = identity$4,
        cache,
        cacheStream,
        projection;

    function reset() {
      cache = cacheStream = null;
      return projection;
    }

    return projection = {
      stream: function stream(_stream) {
        return cache && cacheStream === _stream ? cache : cache = transform$$1(_postclip(cacheStream = _stream));
      },
      postclip: function postclip(_) {
        return arguments.length ? (_postclip = _, x0 = y0 = x1 = y1 = null, reset()) : _postclip;
      },
      clipExtent: function clipExtent(_) {
        return arguments.length ? (_postclip = _ == null ? (x0 = y0 = x1 = y1 = null, identity$4) : clipRectangle(x0 = +_[0][0], y0 = +_[0][1], x1 = +_[1][0], y1 = +_[1][1]), reset()) : x0 == null ? null : [[x0, y0], [x1, y1]];
      },
      scale: function scale(_) {
        return arguments.length ? (transform$$1 = scaleTranslate$1((k = +_) * sx, k * sy, tx, ty), reset()) : k;
      },
      translate: function translate(_) {
        return arguments.length ? (transform$$1 = scaleTranslate$1(k * sx, k * sy, tx = +_[0], ty = +_[1]), reset()) : [tx, ty];
      },
      reflectX: function reflectX(_) {
        return arguments.length ? (transform$$1 = scaleTranslate$1(k * (sx = _ ? -1 : 1), k * sy, tx, ty), reset()) : sx < 0;
      },
      reflectY: function reflectY(_) {
        return arguments.length ? (transform$$1 = scaleTranslate$1(k * sx, k * (sy = _ ? -1 : 1), tx, ty), reset()) : sy < 0;
      },
      fitExtent: function fitExtent$$1(extent, object) {
        return fitExtent(projection, extent, object);
      },
      fitSize: function fitSize$$1(size, object) {
        return fitSize(projection, size, object);
      },
      fitWidth: function fitWidth$$1(width, object) {
        return fitWidth(projection, width, object);
      },
      fitHeight: function fitHeight$$1(height, object) {
        return fitHeight(projection, height, object);
      }
    };
  }

  function naturalEarth1Raw(lambda, phi) {
    var phi2 = phi * phi,
        phi4 = phi2 * phi2;
    return [lambda * (0.8707 - 0.131979 * phi2 + phi4 * (-0.013791 + phi4 * (0.003971 * phi2 - 0.001529 * phi4))), phi * (1.007226 + phi2 * (0.015085 + phi4 * (-0.044475 + 0.028874 * phi2 - 0.005916 * phi4)))];
  }

  naturalEarth1Raw.invert = function (x, y) {
    var phi = y,
        i = 25,
        delta;

    do {
      var phi2 = phi * phi,
          phi4 = phi2 * phi2;
      phi -= delta = (phi * (1.007226 + phi2 * (0.015085 + phi4 * (-0.044475 + 0.028874 * phi2 - 0.005916 * phi4))) - y) / (1.007226 + phi2 * (0.015085 * 3 + phi4 * (-0.044475 * 7 + 0.028874 * 9 * phi2 - 0.005916 * 11 * phi4)));
    } while (abs(delta) > epsilon$2 && --i > 0);

    return [x / (0.8707 + (phi2 = phi * phi) * (-0.131979 + phi2 * (-0.013791 + phi2 * phi2 * phi2 * (0.003971 - 0.001529 * phi2)))), phi];
  };

  function naturalEarth1 () {
    return projection(naturalEarth1Raw).scale(175.295);
  }

  function orthographicRaw(x, y) {
    return [cos$1(y) * sin$1(x), sin$1(y)];
  }
  orthographicRaw.invert = azimuthalInvert(asin);
  function orthographic () {
    return projection(orthographicRaw).scale(249.5).clipAngle(90 + epsilon$2);
  }

  function stereographicRaw(x, y) {
    var cy = cos$1(y),
        k = 1 + cos$1(x) * cy;
    return [cy * sin$1(x) / k, sin$1(y) / k];
  }
  stereographicRaw.invert = azimuthalInvert(function (z) {
    return 2 * atan(z);
  });
  function stereographic () {
    return projection(stereographicRaw).scale(250).clipAngle(142);
  }

  function transverseMercatorRaw(lambda, phi) {
    return [log(tan((halfPi$2 + phi) / 2)), -lambda];
  }

  transverseMercatorRaw.invert = function (x, y) {
    return [-y, 2 * atan(exp(x)) - halfPi$2];
  };

  function transverseMercator () {
    var m = mercatorProjection(transverseMercatorRaw),
        center = m.center,
        rotate = m.rotate;

    m.center = function (_) {
      return arguments.length ? center([-_[1], _[0]]) : (_ = center(), [_[1], -_[0]]);
    };

    m.rotate = function (_) {
      return arguments.length ? rotate([_[0], _[1], _.length > 2 ? _[2] + 90 : 90]) : (_ = rotate(), [_[0], _[1], _[2] - 90]);
    };

    return rotate([0, 0, 90]).scale(159.155);
  }

  function defaultSeparation(a, b) {
    return a.parent === b.parent ? 1 : 2;
  }

  function meanX(children) {
    return children.reduce(meanXReduce, 0) / children.length;
  }

  function meanXReduce(x, c) {
    return x + c.x;
  }

  function maxY(children) {
    return 1 + children.reduce(maxYReduce, 0);
  }

  function maxYReduce(y, c) {
    return Math.max(y, c.y);
  }

  function leafLeft(node) {
    var children;

    while (children = node.children) {
      node = children[0];
    }

    return node;
  }

  function leafRight(node) {
    var children;

    while (children = node.children) {
      node = children[children.length - 1];
    }

    return node;
  }

  function cluster () {
    var separation = defaultSeparation,
        dx = 1,
        dy = 1,
        nodeSize = false;

    function cluster(root) {
      var previousNode,
          x = 0; // First walk, computing the initial x & y values.

      root.eachAfter(function (node) {
        var children = node.children;

        if (children) {
          node.x = meanX(children);
          node.y = maxY(children);
        } else {
          node.x = previousNode ? x += separation(node, previousNode) : 0;
          node.y = 0;
          previousNode = node;
        }
      });
      var left = leafLeft(root),
          right = leafRight(root),
          x0 = left.x - separation(left, right) / 2,
          x1 = right.x + separation(right, left) / 2; // Second walk, normalizing x & y to the desired size.

      return root.eachAfter(nodeSize ? function (node) {
        node.x = (node.x - root.x) * dx;
        node.y = (root.y - node.y) * dy;
      } : function (node) {
        node.x = (node.x - x0) / (x1 - x0) * dx;
        node.y = (1 - (root.y ? node.y / root.y : 1)) * dy;
      });
    }

    cluster.separation = function (x) {
      return arguments.length ? (separation = x, cluster) : separation;
    };

    cluster.size = function (x) {
      return arguments.length ? (nodeSize = false, dx = +x[0], dy = +x[1], cluster) : nodeSize ? null : [dx, dy];
    };

    cluster.nodeSize = function (x) {
      return arguments.length ? (nodeSize = true, dx = +x[0], dy = +x[1], cluster) : nodeSize ? [dx, dy] : null;
    };

    return cluster;
  }

  function count(node) {
    var sum = 0,
        children = node.children,
        i = children && children.length;
    if (!i) sum = 1;else while (--i >= 0) {
      sum += children[i].value;
    }
    node.value = sum;
  }

  function node_count () {
    return this.eachAfter(count);
  }

  function node_each (callback) {
    var node = this,
        current,
        next = [node],
        children,
        i,
        n;

    do {
      current = next.reverse(), next = [];

      while (node = current.pop()) {
        callback(node), children = node.children;
        if (children) for (i = 0, n = children.length; i < n; ++i) {
          next.push(children[i]);
        }
      }
    } while (next.length);

    return this;
  }

  function node_eachBefore (callback) {
    var node = this,
        nodes = [node],
        children,
        i;

    while (node = nodes.pop()) {
      callback(node), children = node.children;
      if (children) for (i = children.length - 1; i >= 0; --i) {
        nodes.push(children[i]);
      }
    }

    return this;
  }

  function node_eachAfter (callback) {
    var node = this,
        nodes = [node],
        next = [],
        children,
        i,
        n;

    while (node = nodes.pop()) {
      next.push(node), children = node.children;
      if (children) for (i = 0, n = children.length; i < n; ++i) {
        nodes.push(children[i]);
      }
    }

    while (node = next.pop()) {
      callback(node);
    }

    return this;
  }

  function node_sum (value) {
    return this.eachAfter(function (node) {
      var sum = +value(node.data) || 0,
          children = node.children,
          i = children && children.length;

      while (--i >= 0) {
        sum += children[i].value;
      }

      node.value = sum;
    });
  }

  function node_sort (compare) {
    return this.eachBefore(function (node) {
      if (node.children) {
        node.children.sort(compare);
      }
    });
  }

  function node_path (end) {
    var start = this,
        ancestor = leastCommonAncestor(start, end),
        nodes = [start];

    while (start !== ancestor) {
      start = start.parent;
      nodes.push(start);
    }

    var k = nodes.length;

    while (end !== ancestor) {
      nodes.splice(k, 0, end);
      end = end.parent;
    }

    return nodes;
  }

  function leastCommonAncestor(a, b) {
    if (a === b) return a;
    var aNodes = a.ancestors(),
        bNodes = b.ancestors(),
        c = null;
    a = aNodes.pop();
    b = bNodes.pop();

    while (a === b) {
      c = a;
      a = aNodes.pop();
      b = bNodes.pop();
    }

    return c;
  }

  function node_ancestors () {
    var node = this,
        nodes = [node];

    while (node = node.parent) {
      nodes.push(node);
    }

    return nodes;
  }

  function node_descendants () {
    var nodes = [];
    this.each(function (node) {
      nodes.push(node);
    });
    return nodes;
  }

  function node_leaves () {
    var leaves = [];
    this.eachBefore(function (node) {
      if (!node.children) {
        leaves.push(node);
      }
    });
    return leaves;
  }

  function node_links () {
    var root = this,
        links = [];
    root.each(function (node) {
      if (node !== root) {
        // DonвЂ™t include the rootвЂ™s parent, if any.
        links.push({
          source: node.parent,
          target: node
        });
      }
    });
    return links;
  }

  function hierarchy(data, children) {
    var root = new Node(data),
        valued = +data.value && (root.value = data.value),
        node,
        nodes = [root],
        child,
        childs,
        i,
        n;
    if (children == null) children = defaultChildren;

    while (node = nodes.pop()) {
      if (valued) node.value = +node.data.value;

      if ((childs = children(node.data)) && (n = childs.length)) {
        node.children = new Array(n);

        for (i = n - 1; i >= 0; --i) {
          nodes.push(child = node.children[i] = new Node(childs[i]));
          child.parent = node;
          child.depth = node.depth + 1;
        }
      }
    }

    return root.eachBefore(computeHeight);
  }

  function node_copy() {
    return hierarchy(this).eachBefore(copyData);
  }

  function defaultChildren(d) {
    return d.children;
  }

  function copyData(node) {
    node.data = node.data.data;
  }

  function computeHeight(node) {
    var height = 0;

    do {
      node.height = height;
    } while ((node = node.parent) && node.height < ++height);
  }
  function Node(data) {
    this.data = data;
    this.depth = this.height = 0;
    this.parent = null;
  }
  Node.prototype = hierarchy.prototype = {
    constructor: Node,
    count: node_count,
    each: node_each,
    eachAfter: node_eachAfter,
    eachBefore: node_eachBefore,
    sum: node_sum,
    sort: node_sort,
    path: node_path,
    ancestors: node_ancestors,
    descendants: node_descendants,
    leaves: node_leaves,
    links: node_links,
    copy: node_copy
  };

  var slice$4 = Array.prototype.slice;
  function shuffle$1(array) {
    var m = array.length,
        t,
        i;

    while (m) {
      i = Math.random() * m-- | 0;
      t = array[m];
      array[m] = array[i];
      array[i] = t;
    }

    return array;
  }

  function enclose (circles) {
    var i = 0,
        n = (circles = shuffle$1(slice$4.call(circles))).length,
        B = [],
        p,
        e;

    while (i < n) {
      p = circles[i];
      if (e && enclosesWeak(e, p)) ++i;else e = encloseBasis(B = extendBasis(B, p)), i = 0;
    }

    return e;
  }

  function extendBasis(B, p) {
    var i, j;
    if (enclosesWeakAll(p, B)) return [p]; // If we get here then B must have at least one element.

    for (i = 0; i < B.length; ++i) {
      if (enclosesNot(p, B[i]) && enclosesWeakAll(encloseBasis2(B[i], p), B)) {
        return [B[i], p];
      }
    } // If we get here then B must have at least two elements.


    for (i = 0; i < B.length - 1; ++i) {
      for (j = i + 1; j < B.length; ++j) {
        if (enclosesNot(encloseBasis2(B[i], B[j]), p) && enclosesNot(encloseBasis2(B[i], p), B[j]) && enclosesNot(encloseBasis2(B[j], p), B[i]) && enclosesWeakAll(encloseBasis3(B[i], B[j], p), B)) {
          return [B[i], B[j], p];
        }
      }
    } // If we get here then something is very wrong.


    throw new Error();
  }

  function enclosesNot(a, b) {
    var dr = a.r - b.r,
        dx = b.x - a.x,
        dy = b.y - a.y;
    return dr < 0 || dr * dr < dx * dx + dy * dy;
  }

  function enclosesWeak(a, b) {
    var dr = a.r - b.r + 1e-6,
        dx = b.x - a.x,
        dy = b.y - a.y;
    return dr > 0 && dr * dr > dx * dx + dy * dy;
  }

  function enclosesWeakAll(a, B) {
    for (var i = 0; i < B.length; ++i) {
      if (!enclosesWeak(a, B[i])) {
        return false;
      }
    }

    return true;
  }

  function encloseBasis(B) {
    switch (B.length) {
      case 1:
        return encloseBasis1(B[0]);

      case 2:
        return encloseBasis2(B[0], B[1]);

      case 3:
        return encloseBasis3(B[0], B[1], B[2]);
    }
  }

  function encloseBasis1(a) {
    return {
      x: a.x,
      y: a.y,
      r: a.r
    };
  }

  function encloseBasis2(a, b) {
    var x1 = a.x,
        y1 = a.y,
        r1 = a.r,
        x2 = b.x,
        y2 = b.y,
        r2 = b.r,
        x21 = x2 - x1,
        y21 = y2 - y1,
        r21 = r2 - r1,
        l = Math.sqrt(x21 * x21 + y21 * y21);
    return {
      x: (x1 + x2 + x21 / l * r21) / 2,
      y: (y1 + y2 + y21 / l * r21) / 2,
      r: (l + r1 + r2) / 2
    };
  }

  function encloseBasis3(a, b, c) {
    var x1 = a.x,
        y1 = a.y,
        r1 = a.r,
        x2 = b.x,
        y2 = b.y,
        r2 = b.r,
        x3 = c.x,
        y3 = c.y,
        r3 = c.r,
        a2 = x1 - x2,
        a3 = x1 - x3,
        b2 = y1 - y2,
        b3 = y1 - y3,
        c2 = r2 - r1,
        c3 = r3 - r1,
        d1 = x1 * x1 + y1 * y1 - r1 * r1,
        d2 = d1 - x2 * x2 - y2 * y2 + r2 * r2,
        d3 = d1 - x3 * x3 - y3 * y3 + r3 * r3,
        ab = a3 * b2 - a2 * b3,
        xa = (b2 * d3 - b3 * d2) / (ab * 2) - x1,
        xb = (b3 * c2 - b2 * c3) / ab,
        ya = (a3 * d2 - a2 * d3) / (ab * 2) - y1,
        yb = (a2 * c3 - a3 * c2) / ab,
        A = xb * xb + yb * yb - 1,
        B = 2 * (r1 + xa * xb + ya * yb),
        C = xa * xa + ya * ya - r1 * r1,
        r = -(A ? (B + Math.sqrt(B * B - 4 * A * C)) / (2 * A) : C / B);
    return {
      x: x1 + xa + xb * r,
      y: y1 + ya + yb * r,
      r: r
    };
  }

  function place(b, a, c) {
    var dx = b.x - a.x,
        x,
        a2,
        dy = b.y - a.y,
        y,
        b2,
        d2 = dx * dx + dy * dy;

    if (d2) {
      a2 = a.r + c.r, a2 *= a2;
      b2 = b.r + c.r, b2 *= b2;

      if (a2 > b2) {
        x = (d2 + b2 - a2) / (2 * d2);
        y = Math.sqrt(Math.max(0, b2 / d2 - x * x));
        c.x = b.x - x * dx - y * dy;
        c.y = b.y - x * dy + y * dx;
      } else {
        x = (d2 + a2 - b2) / (2 * d2);
        y = Math.sqrt(Math.max(0, a2 / d2 - x * x));
        c.x = a.x + x * dx - y * dy;
        c.y = a.y + x * dy + y * dx;
      }
    } else {
      c.x = a.x + c.r;
      c.y = a.y;
    }
  }

  function intersects(a, b) {
    var dr = a.r + b.r - 1e-6,
        dx = b.x - a.x,
        dy = b.y - a.y;
    return dr > 0 && dr * dr > dx * dx + dy * dy;
  }

  function score(node) {
    var a = node._,
        b = node.next._,
        ab = a.r + b.r,
        dx = (a.x * b.r + b.x * a.r) / ab,
        dy = (a.y * b.r + b.y * a.r) / ab;
    return dx * dx + dy * dy;
  }

  function Node$1(circle) {
    this._ = circle;
    this.next = null;
    this.previous = null;
  }

  function packEnclose(circles) {
    if (!(n = circles.length)) return 0;
    var a, b, c, n, aa, ca, i, j, k, sj, sk; // Place the first circle.

    a = circles[0], a.x = 0, a.y = 0;
    if (!(n > 1)) return a.r; // Place the second circle.

    b = circles[1], a.x = -b.r, b.x = a.r, b.y = 0;
    if (!(n > 2)) return a.r + b.r; // Place the third circle.

    place(b, a, c = circles[2]); // Initialize the front-chain using the first three circles a, b and c.

    a = new Node$1(a), b = new Node$1(b), c = new Node$1(c);
    a.next = c.previous = b;
    b.next = a.previous = c;
    c.next = b.previous = a; // Attempt to place each remaining circle…

    pack: for (i = 3; i < n; ++i) {
      place(a._, b._, c = circles[i]), c = new Node$1(c); // Find the closest intersecting circle on the front-chain, if any.
      // “Closeness” is determined by linear distance along the front-chain.
      // “Ahead” or “behind” is likewise determined by linear distance.

      j = b.next, k = a.previous, sj = b._.r, sk = a._.r;

      do {
        if (sj <= sk) {
          if (intersects(j._, c._)) {
            b = j, a.next = b, b.previous = a, --i;
            continue pack;
          }

          sj += j._.r, j = j.next;
        } else {
          if (intersects(k._, c._)) {
            a = k, a.next = b, b.previous = a, --i;
            continue pack;
          }

          sk += k._.r, k = k.previous;
        }
      } while (j !== k.next); // Success! Insert the new circle c between a and b.


      c.previous = a, c.next = b, a.next = b.previous = b = c; // Compute the new closest circle pair to the centroid.

      aa = score(a);

      while ((c = c.next) !== b) {
        if ((ca = score(c)) < aa) {
          a = c, aa = ca;
        }
      }

      b = a.next;
    } // Compute the enclosing circle of the front chain.


    a = [b._], c = b;

    while ((c = c.next) !== b) {
      a.push(c._);
    }

    c = enclose(a); // Translate the circles to put the enclosing circle around the origin.

    for (i = 0; i < n; ++i) {
      a = circles[i], a.x -= c.x, a.y -= c.y;
    }

    return c.r;
  }
  function siblings (circles) {
    packEnclose(circles);
    return circles;
  }

  function optional(f) {
    return f == null ? null : required(f);
  }
  function required(f) {
    if (typeof f !== "function") throw new Error();
    return f;
  }

  function constantZero() {
    return 0;
  }
  function constant$9 (x) {
    return function () {
      return x;
    };
  }

  function defaultRadius$1(d) {
    return Math.sqrt(d.value);
  }

  function index$2 () {
    var radius = null,
        dx = 1,
        dy = 1,
        padding = constantZero;

    function pack(root) {
      root.x = dx / 2, root.y = dy / 2;

      if (radius) {
        root.eachBefore(radiusLeaf(radius)).eachAfter(packChildren(padding, 0.5)).eachBefore(translateChild(1));
      } else {
        root.eachBefore(radiusLeaf(defaultRadius$1)).eachAfter(packChildren(constantZero, 1)).eachAfter(packChildren(padding, root.r / Math.min(dx, dy))).eachBefore(translateChild(Math.min(dx, dy) / (2 * root.r)));
      }

      return root;
    }

    pack.radius = function (x) {
      return arguments.length ? (radius = optional(x), pack) : radius;
    };

    pack.size = function (x) {
      return arguments.length ? (dx = +x[0], dy = +x[1], pack) : [dx, dy];
    };

    pack.padding = function (x) {
      return arguments.length ? (padding = typeof x === "function" ? x : constant$9(+x), pack) : padding;
    };

    return pack;
  }

  function radiusLeaf(radius) {
    return function (node) {
      if (!node.children) {
        node.r = Math.max(0, +radius(node) || 0);
      }
    };
  }

  function packChildren(padding, k) {
    return function (node) {
      if (children = node.children) {
        var children,
            i,
            n = children.length,
            r = padding(node) * k || 0,
            e;
        if (r) for (i = 0; i < n; ++i) {
          children[i].r += r;
        }
        e = packEnclose(children);
        if (r) for (i = 0; i < n; ++i) {
          children[i].r -= r;
        }
        node.r = e + r;
      }
    };
  }

  function translateChild(k) {
    return function (node) {
      var parent = node.parent;
      node.r *= k;

      if (parent) {
        node.x = parent.x + k * node.x;
        node.y = parent.y + k * node.y;
      }
    };
  }

  function roundNode (node) {
    node.x0 = Math.round(node.x0);
    node.y0 = Math.round(node.y0);
    node.x1 = Math.round(node.x1);
    node.y1 = Math.round(node.y1);
  }

  function treemapDice (parent, x0, y0, x1, y1) {
    var nodes = parent.children,
        node,
        i = -1,
        n = nodes.length,
        k = parent.value && (x1 - x0) / parent.value;

    while (++i < n) {
      node = nodes[i], node.y0 = y0, node.y1 = y1;
      node.x0 = x0, node.x1 = x0 += node.value * k;
    }
  }

  function partition () {
    var dx = 1,
        dy = 1,
        padding = 0,
        round = false;

    function partition(root) {
      var n = root.height + 1;
      root.x0 = root.y0 = padding;
      root.x1 = dx;
      root.y1 = dy / n;
      root.eachBefore(positionNode(dy, n));
      if (round) root.eachBefore(roundNode);
      return root;
    }

    function positionNode(dy, n) {
      return function (node) {
        if (node.children) {
          treemapDice(node, node.x0, dy * (node.depth + 1) / n, node.x1, dy * (node.depth + 2) / n);
        }

        var x0 = node.x0,
            y0 = node.y0,
            x1 = node.x1 - padding,
            y1 = node.y1 - padding;
        if (x1 < x0) x0 = x1 = (x0 + x1) / 2;
        if (y1 < y0) y0 = y1 = (y0 + y1) / 2;
        node.x0 = x0;
        node.y0 = y0;
        node.x1 = x1;
        node.y1 = y1;
      };
    }

    partition.round = function (x) {
      return arguments.length ? (round = !!x, partition) : round;
    };

    partition.size = function (x) {
      return arguments.length ? (dx = +x[0], dy = +x[1], partition) : [dx, dy];
    };

    partition.padding = function (x) {
      return arguments.length ? (padding = +x, partition) : padding;
    };

    return partition;
  }

  var keyPrefix$1 = "$",
      // Protect against keys like вЂњ__proto__вЂќ.
  preroot = {
    depth: -1
  },
      ambiguous = {};

  function defaultId(d) {
    return d.id;
  }

  function defaultParentId(d) {
    return d.parentId;
  }

  function stratify () {
    var id = defaultId,
        parentId = defaultParentId;

    function stratify(data) {
      var d,
          i,
          n = data.length,
          root,
          parent,
          node,
          nodes = new Array(n),
          nodeId,
          nodeKey,
          nodeByKey = {};

      for (i = 0; i < n; ++i) {
        d = data[i], node = nodes[i] = new Node(d);

        if ((nodeId = id(d, i, data)) != null && (nodeId += "")) {
          nodeKey = keyPrefix$1 + (node.id = nodeId);
          nodeByKey[nodeKey] = nodeKey in nodeByKey ? ambiguous : node;
        }
      }

      for (i = 0; i < n; ++i) {
        node = nodes[i], nodeId = parentId(data[i], i, data);

        if (nodeId == null || !(nodeId += "")) {
          if (root) throw new Error("multiple roots");
          root = node;
        } else {
          parent = nodeByKey[keyPrefix$1 + nodeId];
          if (!parent) throw new Error("missing: " + nodeId);
          if (parent === ambiguous) throw new Error("ambiguous: " + nodeId);
          if (parent.children) parent.children.push(node);else parent.children = [node];
          node.parent = parent;
        }
      }

      if (!root) throw new Error("no root");
      root.parent = preroot;
      root.eachBefore(function (node) {
        node.depth = node.parent.depth + 1;
        --n;
      }).eachBefore(computeHeight);
      root.parent = null;
      if (n > 0) throw new Error("cycle");
      return root;
    }

    stratify.id = function (x) {
      return arguments.length ? (id = required(x), stratify) : id;
    };

    stratify.parentId = function (x) {
      return arguments.length ? (parentId = required(x), stratify) : parentId;
    };

    return stratify;
  }

  function defaultSeparation$1(a, b) {
    return a.parent === b.parent ? 1 : 2;
  } // function radialSeparation(a, b) {
  //   return (a.parent === b.parent ? 1 : 2) / a.depth;
  // }
  // This function is used to traverse the left contour of a subtree (or
  // subforest). It returns the successor of v on this contour. This successor is
  // either given by the leftmost child of v or by the thread of v. The function
  // returns null if and only if v is on the highest level of its subtree.


  function nextLeft(v) {
    var children = v.children;
    return children ? children[0] : v.t;
  } // This function works analogously to nextLeft.


  function nextRight(v) {
    var children = v.children;
    return children ? children[children.length - 1] : v.t;
  } // Shifts the current subtree rooted at w+. This is done by increasing
  // prelim(w+) and mod(w+) by shift.


  function moveSubtree(wm, wp, shift) {
    var change = shift / (wp.i - wm.i);
    wp.c -= change;
    wp.s += shift;
    wm.c += change;
    wp.z += shift;
    wp.m += shift;
  } // All other shifts, applied to the smaller subtrees between w- and w+, are
  // performed by this function. To prepare the shifts, we have to adjust
  // change(w+), shift(w+), and change(w-).


  function executeShifts(v) {
    var shift = 0,
        change = 0,
        children = v.children,
        i = children.length,
        w;

    while (--i >= 0) {
      w = children[i];
      w.z += shift;
      w.m += shift;
      shift += w.s + (change += w.c);
    }
  } // If vi-вЂ™s ancestor is a sibling of v, returns vi-вЂ™s ancestor. Otherwise,
  // returns the specified (default) ancestor.


  function nextAncestor(vim, v, ancestor) {
    return vim.a.parent === v.parent ? vim.a : ancestor;
  }

  function TreeNode(node, i) {
    this._ = node;
    this.parent = null;
    this.children = null;
    this.A = null; // default ancestor

    this.a = this; // ancestor

    this.z = 0; // prelim

    this.m = 0; // mod

    this.c = 0; // change

    this.s = 0; // shift

    this.t = null; // thread

    this.i = i; // number
  }

  TreeNode.prototype = Object.create(Node.prototype);

  function treeRoot(root) {
    var tree = new TreeNode(root, 0),
        node,
        nodes = [tree],
        child,
        children,
        i,
        n;

    while (node = nodes.pop()) {
      if (children = node._.children) {
        node.children = new Array(n = children.length);

        for (i = n - 1; i >= 0; --i) {
          nodes.push(child = node.children[i] = new TreeNode(children[i], i));
          child.parent = node;
        }
      }
    }

    (tree.parent = new TreeNode(null, 0)).children = [tree];
    return tree;
  } // Node-link tree diagram using the Reingold-Tilford "tidy" algorithm


  function tree () {
    var separation = defaultSeparation$1,
        dx = 1,
        dy = 1,
        nodeSize = null;

    function tree(root) {
      var t = treeRoot(root); // Compute the layout using Buchheim et al.вЂ™s algorithm.

      t.eachAfter(firstWalk), t.parent.m = -t.z;
      t.eachBefore(secondWalk); // If a fixed node size is specified, scale x and y.

      if (nodeSize) root.eachBefore(sizeNode); // If a fixed tree size is specified, scale x and y based on the extent.
      // Compute the left-most, right-most, and depth-most nodes for extents.
      else {
          var left = root,
              right = root,
              bottom = root;
          root.eachBefore(function (node) {
            if (node.x < left.x) left = node;
            if (node.x > right.x) right = node;
            if (node.depth > bottom.depth) bottom = node;
          });
          var s = left === right ? 1 : separation(left, right) / 2,
              tx = s - left.x,
              kx = dx / (right.x + s + tx),
              ky = dy / (bottom.depth || 1);
          root.eachBefore(function (node) {
            node.x = (node.x + tx) * kx;
            node.y = node.depth * ky;
          });
        }
      return root;
    } // Computes a preliminary x-coordinate for v. Before that, FIRST WALK is
    // applied recursively to the children of v, as well as the function
    // APPORTION. After spacing out the children by calling EXECUTE SHIFTS, the
    // node v is placed to the midpoint of its outermost children.


    function firstWalk(v) {
      var children = v.children,
          siblings = v.parent.children,
          w = v.i ? siblings[v.i - 1] : null;

      if (children) {
        executeShifts(v);
        var midpoint = (children[0].z + children[children.length - 1].z) / 2;

        if (w) {
          v.z = w.z + separation(v._, w._);
          v.m = v.z - midpoint;
        } else {
          v.z = midpoint;
        }
      } else if (w) {
        v.z = w.z + separation(v._, w._);
      }

      v.parent.A = apportion(v, w, v.parent.A || siblings[0]);
    } // Computes all real x-coordinates by summing up the modifiers recursively.


    function secondWalk(v) {
      v._.x = v.z + v.parent.m;
      v.m += v.parent.m;
    } // The core of the algorithm. Here, a new subtree is combined with the
    // previous subtrees. Threads are used to traverse the inside and outside
    // contours of the left and right subtree up to the highest common level. The
    // vertices used for the traversals are vi+, vi-, vo-, and vo+, where the
    // superscript o means outside and i means inside, the subscript - means left
    // subtree and + means right subtree. For summing up the modifiers along the
    // contour, we use respective variables si+, si-, so-, and so+. Whenever two
    // nodes of the inside contours conflict, we compute the left one of the
    // greatest uncommon ancestors using the function ANCESTOR and call MOVE
    // SUBTREE to shift the subtree and prepare the shifts of smaller subtrees.
    // Finally, we add a new thread (if necessary).


    function apportion(v, w, ancestor) {
      if (w) {
        var vip = v,
            vop = v,
            vim = w,
            vom = vip.parent.children[0],
            sip = vip.m,
            sop = vop.m,
            sim = vim.m,
            som = vom.m,
            shift;

        while (vim = nextRight(vim), vip = nextLeft(vip), vim && vip) {
          vom = nextLeft(vom);
          vop = nextRight(vop);
          vop.a = v;
          shift = vim.z + sim - vip.z - sip + separation(vim._, vip._);

          if (shift > 0) {
            moveSubtree(nextAncestor(vim, v, ancestor), v, shift);
            sip += shift;
            sop += shift;
          }

          sim += vim.m;
          sip += vip.m;
          som += vom.m;
          sop += vop.m;
        }

        if (vim && !nextRight(vop)) {
          vop.t = vim;
          vop.m += sim - sop;
        }

        if (vip && !nextLeft(vom)) {
          vom.t = vip;
          vom.m += sip - som;
          ancestor = v;
        }
      }

      return ancestor;
    }

    function sizeNode(node) {
      node.x *= dx;
      node.y = node.depth * dy;
    }

    tree.separation = function (x) {
      return arguments.length ? (separation = x, tree) : separation;
    };

    tree.size = function (x) {
      return arguments.length ? (nodeSize = false, dx = +x[0], dy = +x[1], tree) : nodeSize ? null : [dx, dy];
    };

    tree.nodeSize = function (x) {
      return arguments.length ? (nodeSize = true, dx = +x[0], dy = +x[1], tree) : nodeSize ? [dx, dy] : null;
    };

    return tree;
  }

  function treemapSlice (parent, x0, y0, x1, y1) {
    var nodes = parent.children,
        node,
        i = -1,
        n = nodes.length,
        k = parent.value && (y1 - y0) / parent.value;

    while (++i < n) {
      node = nodes[i], node.x0 = x0, node.x1 = x1;
      node.y0 = y0, node.y1 = y0 += node.value * k;
    }
  }

  var phi = (1 + Math.sqrt(5)) / 2;
  function squarifyRatio(ratio, parent, x0, y0, x1, y1) {
    var rows = [],
        nodes = parent.children,
        row,
        nodeValue,
        i0 = 0,
        i1 = 0,
        n = nodes.length,
        dx,
        dy,
        value = parent.value,
        sumValue,
        minValue,
        maxValue,
        newRatio,
        minRatio,
        alpha,
        beta;

    while (i0 < n) {
      dx = x1 - x0, dy = y1 - y0; // Find the next non-empty node.

      do {
        sumValue = nodes[i1++].value;
      } while (!sumValue && i1 < n);

      minValue = maxValue = sumValue;
      alpha = Math.max(dy / dx, dx / dy) / (value * ratio);
      beta = sumValue * sumValue * alpha;
      minRatio = Math.max(maxValue / beta, beta / minValue); // Keep adding nodes while the aspect ratio maintains or improves.

      for (; i1 < n; ++i1) {
        sumValue += nodeValue = nodes[i1].value;
        if (nodeValue < minValue) minValue = nodeValue;
        if (nodeValue > maxValue) maxValue = nodeValue;
        beta = sumValue * sumValue * alpha;
        newRatio = Math.max(maxValue / beta, beta / minValue);

        if (newRatio > minRatio) {
          sumValue -= nodeValue;
          break;
        }

        minRatio = newRatio;
      } // Position and record the row orientation.


      rows.push(row = {
        value: sumValue,
        dice: dx < dy,
        children: nodes.slice(i0, i1)
      });
      if (row.dice) treemapDice(row, x0, y0, x1, value ? y0 += dy * sumValue / value : y1);else treemapSlice(row, x0, y0, value ? x0 += dx * sumValue / value : x1, y1);
      value -= sumValue, i0 = i1;
    }

    return rows;
  }
  var squarify = (function custom(ratio) {
    function squarify(parent, x0, y0, x1, y1) {
      squarifyRatio(ratio, parent, x0, y0, x1, y1);
    }

    squarify.ratio = function (x) {
      return custom((x = +x) > 1 ? x : 1);
    };

    return squarify;
  })(phi);

  function index$3 () {
    var tile = squarify,
        round = false,
        dx = 1,
        dy = 1,
        paddingStack = [0],
        paddingInner = constantZero,
        paddingTop = constantZero,
        paddingRight = constantZero,
        paddingBottom = constantZero,
        paddingLeft = constantZero;

    function treemap(root) {
      root.x0 = root.y0 = 0;
      root.x1 = dx;
      root.y1 = dy;
      root.eachBefore(positionNode);
      paddingStack = [0];
      if (round) root.eachBefore(roundNode);
      return root;
    }

    function positionNode(node) {
      var p = paddingStack[node.depth],
          x0 = node.x0 + p,
          y0 = node.y0 + p,
          x1 = node.x1 - p,
          y1 = node.y1 - p;
      if (x1 < x0) x0 = x1 = (x0 + x1) / 2;
      if (y1 < y0) y0 = y1 = (y0 + y1) / 2;
      node.x0 = x0;
      node.y0 = y0;
      node.x1 = x1;
      node.y1 = y1;

      if (node.children) {
        p = paddingStack[node.depth + 1] = paddingInner(node) / 2;
        x0 += paddingLeft(node) - p;
        y0 += paddingTop(node) - p;
        x1 -= paddingRight(node) - p;
        y1 -= paddingBottom(node) - p;
        if (x1 < x0) x0 = x1 = (x0 + x1) / 2;
        if (y1 < y0) y0 = y1 = (y0 + y1) / 2;
        tile(node, x0, y0, x1, y1);
      }
    }

    treemap.round = function (x) {
      return arguments.length ? (round = !!x, treemap) : round;
    };

    treemap.size = function (x) {
      return arguments.length ? (dx = +x[0], dy = +x[1], treemap) : [dx, dy];
    };

    treemap.tile = function (x) {
      return arguments.length ? (tile = required(x), treemap) : tile;
    };

    treemap.padding = function (x) {
      return arguments.length ? treemap.paddingInner(x).paddingOuter(x) : treemap.paddingInner();
    };

    treemap.paddingInner = function (x) {
      return arguments.length ? (paddingInner = typeof x === "function" ? x : constant$9(+x), treemap) : paddingInner;
    };

    treemap.paddingOuter = function (x) {
      return arguments.length ? treemap.paddingTop(x).paddingRight(x).paddingBottom(x).paddingLeft(x) : treemap.paddingTop();
    };

    treemap.paddingTop = function (x) {
      return arguments.length ? (paddingTop = typeof x === "function" ? x : constant$9(+x), treemap) : paddingTop;
    };

    treemap.paddingRight = function (x) {
      return arguments.length ? (paddingRight = typeof x === "function" ? x : constant$9(+x), treemap) : paddingRight;
    };

    treemap.paddingBottom = function (x) {
      return arguments.length ? (paddingBottom = typeof x === "function" ? x : constant$9(+x), treemap) : paddingBottom;
    };

    treemap.paddingLeft = function (x) {
      return arguments.length ? (paddingLeft = typeof x === "function" ? x : constant$9(+x), treemap) : paddingLeft;
    };

    return treemap;
  }

  function binary (parent, x0, y0, x1, y1) {
    var nodes = parent.children,
        i,
        n = nodes.length,
        sum,
        sums = new Array(n + 1);

    for (sums[0] = sum = i = 0; i < n; ++i) {
      sums[i + 1] = sum += nodes[i].value;
    }

    partition(0, n, parent.value, x0, y0, x1, y1);

    function partition(i, j, value, x0, y0, x1, y1) {
      if (i >= j - 1) {
        var node = nodes[i];
        node.x0 = x0, node.y0 = y0;
        node.x1 = x1, node.y1 = y1;
        return;
      }

      var valueOffset = sums[i],
          valueTarget = value / 2 + valueOffset,
          k = i + 1,
          hi = j - 1;

      while (k < hi) {
        var mid = k + hi >>> 1;
        if (sums[mid] < valueTarget) k = mid + 1;else hi = mid;
      }

      if (valueTarget - sums[k - 1] < sums[k] - valueTarget && i + 1 < k) --k;
      var valueLeft = sums[k] - valueOffset,
          valueRight = value - valueLeft;

      if (x1 - x0 > y1 - y0) {
        var xk = (x0 * valueRight + x1 * valueLeft) / value;
        partition(i, k, valueLeft, x0, y0, xk, y1);
        partition(k, j, valueRight, xk, y0, x1, y1);
      } else {
        var yk = (y0 * valueRight + y1 * valueLeft) / value;
        partition(i, k, valueLeft, x0, y0, x1, yk);
        partition(k, j, valueRight, x0, yk, x1, y1);
      }
    }
  }

  function sliceDice (parent, x0, y0, x1, y1) {
    (parent.depth & 1 ? treemapSlice : treemapDice)(parent, x0, y0, x1, y1);
  }

  var resquarify = (function custom(ratio) {
    function resquarify(parent, x0, y0, x1, y1) {
      if ((rows = parent._squarify) && rows.ratio === ratio) {
        var rows,
            row,
            nodes,
            i,
            j = -1,
            n,
            m = rows.length,
            value = parent.value;

        while (++j < m) {
          row = rows[j], nodes = row.children;

          for (i = row.value = 0, n = nodes.length; i < n; ++i) {
            row.value += nodes[i].value;
          }

          if (row.dice) treemapDice(row, x0, y0, x1, y0 += (y1 - y0) * row.value / value);else treemapSlice(row, x0, y0, x0 += (x1 - x0) * row.value / value, y1);
          value -= row.value;
        }
      } else {
        parent._squarify = rows = squarifyRatio(ratio, parent, x0, y0, x1, y1);
        rows.ratio = ratio;
      }
    }

    resquarify.ratio = function (x) {
      return custom((x = +x) > 1 ? x : 1);
    };

    return resquarify;
  })(phi);

  function area$2 (polygon) {
    var i = -1,
        n = polygon.length,
        a,
        b = polygon[n - 1],
        area = 0;

    while (++i < n) {
      a = b;
      b = polygon[i];
      area += a[1] * b[0] - a[0] * b[1];
    }

    return area / 2;
  }

  function centroid$1 (polygon) {
    var i = -1,
        n = polygon.length,
        x = 0,
        y = 0,
        a,
        b = polygon[n - 1],
        c,
        k = 0;

    while (++i < n) {
      a = b;
      b = polygon[i];
      k += c = a[0] * b[1] - b[0] * a[1];
      x += (a[0] + b[0]) * c;
      y += (a[1] + b[1]) * c;
    }

    return k *= 3, [x / k, y / k];
  }

  // Returns the 2D cross product of AB and AC vectors, i.e., the z-component of
  // the 3D cross product in a quadrant I Cartesian coordinate system (+x is
  // right, +y is up). Returns a positive value if ABC is counter-clockwise,
  function cross$1 (a, b, c) {
    return (b[0] - a[0]) * (c[1] - a[1]) - (b[1] - a[1]) * (c[0] - a[0]);
  }

  function lexicographicOrder(a, b) {
    return a[0] - b[0] || a[1] - b[1];
  } // Computes the upper convex hull per the monotone chain algorithm.
  // Assumes points.length >= 3, is sorted by x, unique in y.
  // Returns an array of indices into points in left-to-right order.


  function computeUpperHullIndexes(points) {
    var n = points.length,
        indexes = [0, 1],
        size = 2;

    for (var i = 2; i < n; ++i) {
      while (size > 1 && cross$1(points[indexes[size - 2]], points[indexes[size - 1]], points[i]) <= 0) {
        --size;
      }

      indexes[size++] = i;
    }

    return indexes.slice(0, size); // remove popped points
  }

  function hull (points) {
    if ((n = points.length) < 3) return null;
    var i,
        n,
        sortedPoints = new Array(n),
        flippedPoints = new Array(n);

    for (i = 0; i < n; ++i) {
      sortedPoints[i] = [+points[i][0], +points[i][1], i];
    }

    sortedPoints.sort(lexicographicOrder);

    for (i = 0; i < n; ++i) {
      flippedPoints[i] = [sortedPoints[i][0], -sortedPoints[i][1]];
    }

    var upperIndexes = computeUpperHullIndexes(sortedPoints),
        lowerIndexes = computeUpperHullIndexes(flippedPoints); // Construct the hull polygon, removing possible duplicate endpoints.

    var skipLeft = lowerIndexes[0] === upperIndexes[0],
        skipRight = lowerIndexes[lowerIndexes.length - 1] === upperIndexes[upperIndexes.length - 1],
        hull = []; // Add upper hull in right-to-l order.
    // Then add lower hull in left-to-right order.

    for (i = upperIndexes.length - 1; i >= 0; --i) {
      hull.push(points[sortedPoints[upperIndexes[i]][2]]);
    }

    for (i = +skipLeft; i < lowerIndexes.length - skipRight; ++i) {
      hull.push(points[sortedPoints[lowerIndexes[i]][2]]);
    }

    return hull;
  }

  function contains$2 (polygon, point) {
    var n = polygon.length,
        p = polygon[n - 1],
        x = point[0],
        y = point[1],
        x0 = p[0],
        y0 = p[1],
        x1,
        y1,
        inside = false;

    for (var i = 0; i < n; ++i) {
      p = polygon[i], x1 = p[0], y1 = p[1];
      if (y1 > y !== y0 > y && x < (x0 - x1) * (y - y1) / (y0 - y1) + x1) inside = !inside;
      x0 = x1, y0 = y1;
    }

    return inside;
  }

  function length$2 (polygon) {
    var i = -1,
        n = polygon.length,
        b = polygon[n - 1],
        xa,
        ya,
        xb = b[0],
        yb = b[1],
        perimeter = 0;

    while (++i < n) {
      xa = xb;
      ya = yb;
      b = polygon[i];
      xb = b[0];
      yb = b[1];
      xa -= xb;
      ya -= yb;
      perimeter += Math.sqrt(xa * xa + ya * ya);
    }

    return perimeter;
  }

  function defaultSource$1 () {
    return Math.random();
  }

  var uniform = (function sourceRandomUniform(source) {
    function randomUniform(min, max) {
      min = min == null ? 0 : +min;
      max = max == null ? 1 : +max;
      if (arguments.length === 1) max = min, min = 0;else max -= min;
      return function () {
        return source() * max + min;
      };
    }

    randomUniform.source = sourceRandomUniform;
    return randomUniform;
  })(defaultSource$1);

  var normal = (function sourceRandomNormal(source) {
    function randomNormal(mu, sigma) {
      var x, r;
      mu = mu == null ? 0 : +mu;
      sigma = sigma == null ? 1 : +sigma;
      return function () {
        var y; // If available, use the second previously-generated uniform random.

        if (x != null) y = x, x = null; // Otherwise, generate a new x and y.
        else do {
            x = source() * 2 - 1;
            y = source() * 2 - 1;
            r = x * x + y * y;
          } while (!r || r > 1);
        return mu + sigma * y * Math.sqrt(-2 * Math.log(r) / r);
      };
    }

    randomNormal.source = sourceRandomNormal;
    return randomNormal;
  })(defaultSource$1);

  var logNormal = (function sourceRandomLogNormal(source) {
    function randomLogNormal() {
      var randomNormal = normal.source(source).apply(this, arguments);
      return function () {
        return Math.exp(randomNormal());
      };
    }

    randomLogNormal.source = sourceRandomLogNormal;
    return randomLogNormal;
  })(defaultSource$1);

  var irwinHall = (function sourceRandomIrwinHall(source) {
    function randomIrwinHall(n) {
      return function () {
        for (var sum = 0, i = 0; i < n; ++i) {
          sum += source();
        }

        return sum;
      };
    }

    randomIrwinHall.source = sourceRandomIrwinHall;
    return randomIrwinHall;
  })(defaultSource$1);

  var bates = (function sourceRandomBates(source) {
    function randomBates(n) {
      var randomIrwinHall = irwinHall.source(source)(n);
      return function () {
        return randomIrwinHall() / n;
      };
    }

    randomBates.source = sourceRandomBates;
    return randomBates;
  })(defaultSource$1);

  var exponential$1 = (function sourceRandomExponential(source) {
    function randomExponential(lambda) {
      return function () {
        return -Math.log(1 - source()) / lambda;
      };
    }

    randomExponential.source = sourceRandomExponential;
    return randomExponential;
  })(defaultSource$1);

  function initRange(domain, range) {
    switch (arguments.length) {
      case 0:
        break;

      case 1:
        this.range(domain);
        break;

      default:
        this.range(range).domain(domain);
        break;
    }

    return this;
  }
  function initInterpolator(domain, interpolator) {
    switch (arguments.length) {
      case 0:
        break;

      case 1:
        this.interpolator(domain);
        break;

      default:
        this.interpolator(interpolator).domain(domain);
        break;
    }

    return this;
  }

  var array$3 = Array.prototype;
  var map$2 = array$3.map;
  var slice$5 = array$3.slice;

  var implicit = {
    name: "implicit"
  };
  function ordinal() {
    var index = map$1(),
        domain = [],
        range = [],
        unknown = implicit;

    function scale(d) {
      var key = d + "",
          i = index.get(key);

      if (!i) {
        if (unknown !== implicit) return unknown;
        index.set(key, i = domain.push(d));
      }

      return range[(i - 1) % range.length];
    }

    scale.domain = function (_) {
      if (!arguments.length) return domain.slice();
      domain = [], index = map$1();
      var i = -1,
          n = _.length,
          d,
          key;

      while (++i < n) {
        if (!index.has(key = (d = _[i]) + "")) index.set(key, domain.push(d));
      }

      return scale;
    };

    scale.range = function (_) {
      return arguments.length ? (range = slice$5.call(_), scale) : range.slice();
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    scale.copy = function () {
      return ordinal(domain, range).unknown(unknown);
    };

    initRange.apply(scale, arguments);
    return scale;
  }

  function band() {
    var scale = ordinal().unknown(undefined),
        domain = scale.domain,
        ordinalRange = scale.range,
        range$$1 = [0, 1],
        step,
        bandwidth,
        round = false,
        paddingInner = 0,
        paddingOuter = 0,
        align = 0.5;
    delete scale.unknown;

    function rescale() {
      var n = domain().length,
          reverse = range$$1[1] < range$$1[0],
          start = range$$1[reverse - 0],
          stop = range$$1[1 - reverse];
      step = (stop - start) / Math.max(1, n - paddingInner + paddingOuter * 2);
      if (round) step = Math.floor(step);
      start += (stop - start - step * (n - paddingInner)) * align;
      bandwidth = step * (1 - paddingInner);
      if (round) start = Math.round(start), bandwidth = Math.round(bandwidth);
      var values = sequence(n).map(function (i) {
        return start + step * i;
      });
      return ordinalRange(reverse ? values.reverse() : values);
    }

    scale.domain = function (_) {
      return arguments.length ? (domain(_), rescale()) : domain();
    };

    scale.range = function (_) {
      return arguments.length ? (range$$1 = [+_[0], +_[1]], rescale()) : range$$1.slice();
    };

    scale.rangeRound = function (_) {
      return range$$1 = [+_[0], +_[1]], round = true, rescale();
    };

    scale.bandwidth = function () {
      return bandwidth;
    };

    scale.step = function () {
      return step;
    };

    scale.round = function (_) {
      return arguments.length ? (round = !!_, rescale()) : round;
    };

    scale.padding = function (_) {
      return arguments.length ? (paddingInner = Math.min(1, paddingOuter = +_), rescale()) : paddingInner;
    };

    scale.paddingInner = function (_) {
      return arguments.length ? (paddingInner = Math.min(1, _), rescale()) : paddingInner;
    };

    scale.paddingOuter = function (_) {
      return arguments.length ? (paddingOuter = +_, rescale()) : paddingOuter;
    };

    scale.align = function (_) {
      return arguments.length ? (align = Math.max(0, Math.min(1, _)), rescale()) : align;
    };

    scale.copy = function () {
      return band(domain(), range$$1).round(round).paddingInner(paddingInner).paddingOuter(paddingOuter).align(align);
    };

    return initRange.apply(rescale(), arguments);
  }

  function pointish(scale) {
    var copy = scale.copy;
    scale.padding = scale.paddingOuter;
    delete scale.paddingInner;
    delete scale.paddingOuter;

    scale.copy = function () {
      return pointish(copy());
    };

    return scale;
  }

  function point$1() {
    return pointish(band.apply(null, arguments).paddingInner(1));
  }

  function constant$a (x) {
    return function () {
      return x;
    };
  }

  function number$2 (x) {
    return +x;
  }

  var unit = [0, 1];
  function identity$6(x) {
    return x;
  }

  function normalize(a, b) {
    return (b -= a = +a) ? function (x) {
      return (x - a) / b;
    } : constant$a(isNaN(b) ? NaN : 0.5);
  }

  function clamper(domain) {
    var a = domain[0],
        b = domain[domain.length - 1],
        t;
    if (a > b) t = a, a = b, b = t;
    return function (x) {
      return Math.max(a, Math.min(b, x));
    };
  } // normalize(a, b)(x) takes a domain value x in [a,b] and returns the corresponding parameter t in [0,1].
  // interpolate(a, b)(t) takes a parameter t in [0,1] and returns the corresponding range value x in [a,b].


  function bimap(domain, range, interpolate$$1) {
    var d0 = domain[0],
        d1 = domain[1],
        r0 = range[0],
        r1 = range[1];
    if (d1 < d0) d0 = normalize(d1, d0), r0 = interpolate$$1(r1, r0);else d0 = normalize(d0, d1), r0 = interpolate$$1(r0, r1);
    return function (x) {
      return r0(d0(x));
    };
  }

  function polymap(domain, range, interpolate$$1) {
    var j = Math.min(domain.length, range.length) - 1,
        d = new Array(j),
        r = new Array(j),
        i = -1; // Reverse descending domains.

    if (domain[j] < domain[0]) {
      domain = domain.slice().reverse();
      range = range.slice().reverse();
    }

    while (++i < j) {
      d[i] = normalize(domain[i], domain[i + 1]);
      r[i] = interpolate$$1(range[i], range[i + 1]);
    }

    return function (x) {
      var i = bisectRight(domain, x, 1, j) - 1;
      return r[i](d[i](x));
    };
  }

  function copy(source, target) {
    return target.domain(source.domain()).range(source.range()).interpolate(source.interpolate()).clamp(source.clamp()).unknown(source.unknown());
  }
  function transformer$1() {
    var domain = unit,
        range = unit,
        interpolate$$1 = interpolateValue,
        transform,
        untransform,
        unknown,
        clamp = identity$6,
        piecewise$$1,
        output,
        input;

    function rescale() {
      piecewise$$1 = Math.min(domain.length, range.length) > 2 ? polymap : bimap;
      output = input = null;
      return scale;
    }

    function scale(x) {
      return isNaN(x = +x) ? unknown : (output || (output = piecewise$$1(domain.map(transform), range, interpolate$$1)))(transform(clamp(x)));
    }

    scale.invert = function (y) {
      return clamp(untransform((input || (input = piecewise$$1(range, domain.map(transform), interpolateNumber)))(y)));
    };

    scale.domain = function (_) {
      return arguments.length ? (domain = map$2.call(_, number$2), clamp === identity$6 || (clamp = clamper(domain)), rescale()) : domain.slice();
    };

    scale.range = function (_) {
      return arguments.length ? (range = slice$5.call(_), rescale()) : range.slice();
    };

    scale.rangeRound = function (_) {
      return range = slice$5.call(_), interpolate$$1 = interpolateRound, rescale();
    };

    scale.clamp = function (_) {
      return arguments.length ? (clamp = _ ? clamper(domain) : identity$6, scale) : clamp !== identity$6;
    };

    scale.interpolate = function (_) {
      return arguments.length ? (interpolate$$1 = _, rescale()) : interpolate$$1;
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    return function (t, u) {
      transform = t, untransform = u;
      return rescale();
    };
  }
  function continuous(transform, untransform) {
    return transformer$1()(transform, untransform);
  }

  function tickFormat (start, stop, count, specifier) {
    var step = tickStep(start, stop, count),
        precision;
    specifier = formatSpecifier(specifier == null ? ",f" : specifier);

    switch (specifier.type) {
      case "s":
        {
          var value = Math.max(Math.abs(start), Math.abs(stop));
          if (specifier.precision == null && !isNaN(precision = precisionPrefix(step, value))) specifier.precision = precision;
          return exports.formatPrefix(specifier, value);
        }

      case "":
      case "e":
      case "g":
      case "p":
      case "r":
        {
          if (specifier.precision == null && !isNaN(precision = precisionRound(step, Math.max(Math.abs(start), Math.abs(stop))))) specifier.precision = precision - (specifier.type === "e");
          break;
        }

      case "f":
      case "%":
        {
          if (specifier.precision == null && !isNaN(precision = precisionFixed(step))) specifier.precision = precision - (specifier.type === "%") * 2;
          break;
        }
    }

    return exports.format(specifier);
  }

  function linearish(scale) {
    var domain = scale.domain;

    scale.ticks = function (count) {
      var d = domain();
      return ticks(d[0], d[d.length - 1], count == null ? 10 : count);
    };

    scale.tickFormat = function (count, specifier) {
      var d = domain();
      return tickFormat(d[0], d[d.length - 1], count == null ? 10 : count, specifier);
    };

    scale.nice = function (count) {
      if (count == null) count = 10;
      var d = domain(),
          i0 = 0,
          i1 = d.length - 1,
          start = d[i0],
          stop = d[i1],
          step;

      if (stop < start) {
        step = start, start = stop, stop = step;
        step = i0, i0 = i1, i1 = step;
      }

      step = tickIncrement(start, stop, count);

      if (step > 0) {
        start = Math.floor(start / step) * step;
        stop = Math.ceil(stop / step) * step;
        step = tickIncrement(start, stop, count);
      } else if (step < 0) {
        start = Math.ceil(start * step) / step;
        stop = Math.floor(stop * step) / step;
        step = tickIncrement(start, stop, count);
      }

      if (step > 0) {
        d[i0] = Math.floor(start / step) * step;
        d[i1] = Math.ceil(stop / step) * step;
        domain(d);
      } else if (step < 0) {
        d[i0] = Math.ceil(start * step) / step;
        d[i1] = Math.floor(stop * step) / step;
        domain(d);
      }

      return scale;
    };

    return scale;
  }
  function linear$2() {
    var scale = continuous(identity$6, identity$6);

    scale.copy = function () {
      return copy(scale, linear$2());
    };

    initRange.apply(scale, arguments);
    return linearish(scale);
  }

  function identity$7(domain) {
    var unknown;

    function scale(x) {
      return isNaN(x = +x) ? unknown : x;
    }

    scale.invert = scale;

    scale.domain = scale.range = function (_) {
      return arguments.length ? (domain = map$2.call(_, number$2), scale) : domain.slice();
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    scale.copy = function () {
      return identity$7(domain).unknown(unknown);
    };

    domain = arguments.length ? map$2.call(domain, number$2) : [0, 1];
    return linearish(scale);
  }

  function nice (domain, interval) {
    domain = domain.slice();
    var i0 = 0,
        i1 = domain.length - 1,
        x0 = domain[i0],
        x1 = domain[i1],
        t;

    if (x1 < x0) {
      t = i0, i0 = i1, i1 = t;
      t = x0, x0 = x1, x1 = t;
    }

    domain[i0] = interval.floor(x0);
    domain[i1] = interval.ceil(x1);
    return domain;
  }

  function transformLog(x) {
    return Math.log(x);
  }

  function transformExp(x) {
    return Math.exp(x);
  }

  function transformLogn(x) {
    return -Math.log(-x);
  }

  function transformExpn(x) {
    return -Math.exp(-x);
  }

  function pow10(x) {
    return isFinite(x) ? +("1e" + x) : x < 0 ? 0 : x;
  }

  function powp(base) {
    return base === 10 ? pow10 : base === Math.E ? Math.exp : function (x) {
      return Math.pow(base, x);
    };
  }

  function logp(base) {
    return base === Math.E ? Math.log : base === 10 && Math.log10 || base === 2 && Math.log2 || (base = Math.log(base), function (x) {
      return Math.log(x) / base;
    });
  }

  function reflect(f) {
    return function (x) {
      return -f(-x);
    };
  }

  function loggish(transform) {
    var scale = transform(transformLog, transformExp),
        domain = scale.domain,
        base = 10,
        logs,
        pows;

    function rescale() {
      logs = logp(base), pows = powp(base);

      if (domain()[0] < 0) {
        logs = reflect(logs), pows = reflect(pows);
        transform(transformLogn, transformExpn);
      } else {
        transform(transformLog, transformExp);
      }

      return scale;
    }

    scale.base = function (_) {
      return arguments.length ? (base = +_, rescale()) : base;
    };

    scale.domain = function (_) {
      return arguments.length ? (domain(_), rescale()) : domain();
    };

    scale.ticks = function (count) {
      var d = domain(),
          u = d[0],
          v = d[d.length - 1],
          r;
      if (r = v < u) i = u, u = v, v = i;
      var i = logs(u),
          j = logs(v),
          p,
          k,
          t,
          n = count == null ? 10 : +count,
          z = [];

      if (!(base % 1) && j - i < n) {
        i = Math.round(i) - 1, j = Math.round(j) + 1;
        if (u > 0) for (; i < j; ++i) {
          for (k = 1, p = pows(i); k < base; ++k) {
            t = p * k;
            if (t < u) continue;
            if (t > v) break;
            z.push(t);
          }
        } else for (; i < j; ++i) {
          for (k = base - 1, p = pows(i); k >= 1; --k) {
            t = p * k;
            if (t < u) continue;
            if (t > v) break;
            z.push(t);
          }
        }
      } else {
        z = ticks(i, j, Math.min(j - i, n)).map(pows);
      }

      return r ? z.reverse() : z;
    };

    scale.tickFormat = function (count, specifier) {
      if (specifier == null) specifier = base === 10 ? ".0e" : ",";
      if (typeof specifier !== "function") specifier = exports.format(specifier);
      if (count === Infinity) return specifier;
      if (count == null) count = 10;
      var k = Math.max(1, base * count / scale.ticks().length); // TODO fast estimate?

      return function (d) {
        var i = d / pows(Math.round(logs(d)));
        if (i * base < base - 0.5) i *= base;
        return i <= k ? specifier(d) : "";
      };
    };

    scale.nice = function () {
      return domain(nice(domain(), {
        floor: function floor(x) {
          return pows(Math.floor(logs(x)));
        },
        ceil: function ceil(x) {
          return pows(Math.ceil(logs(x)));
        }
      }));
    };

    return scale;
  }
  function log$1() {
    var scale = loggish(transformer$1()).domain([1, 10]);

    scale.copy = function () {
      return copy(scale, log$1()).base(scale.base());
    };

    initRange.apply(scale, arguments);
    return scale;
  }

  function transformSymlog(c) {
    return function (x) {
      return Math.sign(x) * Math.log1p(Math.abs(x / c));
    };
  }

  function transformSymexp(c) {
    return function (x) {
      return Math.sign(x) * Math.expm1(Math.abs(x)) * c;
    };
  }

  function symlogish(transform) {
    var c = 1,
        scale = transform(transformSymlog(c), transformSymexp(c));

    scale.constant = function (_) {
      return arguments.length ? transform(transformSymlog(c = +_), transformSymexp(c)) : c;
    };

    return linearish(scale);
  }
  function symlog() {
    var scale = symlogish(transformer$1());

    scale.copy = function () {
      return copy(scale, symlog()).constant(scale.constant());
    };

    return initRange.apply(scale, arguments);
  }

  function transformPow(exponent) {
    return function (x) {
      return x < 0 ? -Math.pow(-x, exponent) : Math.pow(x, exponent);
    };
  }

  function transformSqrt(x) {
    return x < 0 ? -Math.sqrt(-x) : Math.sqrt(x);
  }

  function transformSquare(x) {
    return x < 0 ? -x * x : x * x;
  }

  function powish(transform) {
    var scale = transform(identity$6, identity$6),
        exponent = 1;

    function rescale() {
      return exponent === 1 ? transform(identity$6, identity$6) : exponent === 0.5 ? transform(transformSqrt, transformSquare) : transform(transformPow(exponent), transformPow(1 / exponent));
    }

    scale.exponent = function (_) {
      return arguments.length ? (exponent = +_, rescale()) : exponent;
    };

    return linearish(scale);
  }
  function pow$1() {
    var scale = powish(transformer$1());

    scale.copy = function () {
      return copy(scale, pow$1()).exponent(scale.exponent());
    };

    initRange.apply(scale, arguments);
    return scale;
  }
  function sqrt$1() {
    return pow$1.apply(null, arguments).exponent(0.5);
  }

  function quantile$$1() {
    var domain = [],
        range = [],
        thresholds = [],
        unknown;

    function rescale() {
      var i = 0,
          n = Math.max(1, range.length);
      thresholds = new Array(n - 1);

      while (++i < n) {
        thresholds[i - 1] = threshold(domain, i / n);
      }

      return scale;
    }

    function scale(x) {
      return isNaN(x = +x) ? unknown : range[bisectRight(thresholds, x)];
    }

    scale.invertExtent = function (y) {
      var i = range.indexOf(y);
      return i < 0 ? [NaN, NaN] : [i > 0 ? thresholds[i - 1] : domain[0], i < thresholds.length ? thresholds[i] : domain[domain.length - 1]];
    };

    scale.domain = function (_) {
      if (!arguments.length) return domain.slice();
      domain = [];

      for (var i = 0, n = _.length, d; i < n; ++i) {
        if (d = _[i], d != null && !isNaN(d = +d)) domain.push(d);
      }

      domain.sort(ascending);
      return rescale();
    };

    scale.range = function (_) {
      return arguments.length ? (range = slice$5.call(_), rescale()) : range.slice();
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    scale.quantiles = function () {
      return thresholds.slice();
    };

    scale.copy = function () {
      return quantile$$1().domain(domain).range(range).unknown(unknown);
    };

    return initRange.apply(scale, arguments);
  }

  function quantize$1() {
    var x0 = 0,
        x1 = 1,
        n = 1,
        domain = [0.5],
        range = [0, 1],
        unknown;

    function scale(x) {
      return x <= x ? range[bisectRight(domain, x, 0, n)] : unknown;
    }

    function rescale() {
      var i = -1;
      domain = new Array(n);

      while (++i < n) {
        domain[i] = ((i + 1) * x1 - (i - n) * x0) / (n + 1);
      }

      return scale;
    }

    scale.domain = function (_) {
      return arguments.length ? (x0 = +_[0], x1 = +_[1], rescale()) : [x0, x1];
    };

    scale.range = function (_) {
      return arguments.length ? (n = (range = slice$5.call(_)).length - 1, rescale()) : range.slice();
    };

    scale.invertExtent = function (y) {
      var i = range.indexOf(y);
      return i < 0 ? [NaN, NaN] : i < 1 ? [x0, domain[0]] : i >= n ? [domain[n - 1], x1] : [domain[i - 1], domain[i]];
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : scale;
    };

    scale.thresholds = function () {
      return domain.slice();
    };

    scale.copy = function () {
      return quantize$1().domain([x0, x1]).range(range).unknown(unknown);
    };

    return initRange.apply(linearish(scale), arguments);
  }

  function threshold$1() {
    var domain = [0.5],
        range = [0, 1],
        unknown,
        n = 1;

    function scale(x) {
      return x <= x ? range[bisectRight(domain, x, 0, n)] : unknown;
    }

    scale.domain = function (_) {
      return arguments.length ? (domain = slice$5.call(_), n = Math.min(domain.length, range.length - 1), scale) : domain.slice();
    };

    scale.range = function (_) {
      return arguments.length ? (range = slice$5.call(_), n = Math.min(domain.length, range.length - 1), scale) : range.slice();
    };

    scale.invertExtent = function (y) {
      var i = range.indexOf(y);
      return [domain[i - 1], domain[i]];
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    scale.copy = function () {
      return threshold$1().domain(domain).range(range).unknown(unknown);
    };

    return initRange.apply(scale, arguments);
  }

  var t0$1 = new Date(),
      t1$1 = new Date();
  function newInterval(floori, offseti, count, field) {
    function interval(date) {
      return floori(date = new Date(+date)), date;
    }

    interval.floor = interval;

    interval.ceil = function (date) {
      return floori(date = new Date(date - 1)), offseti(date, 1), floori(date), date;
    };

    interval.round = function (date) {
      var d0 = interval(date),
          d1 = interval.ceil(date);
      return date - d0 < d1 - date ? d0 : d1;
    };

    interval.offset = function (date, step) {
      return offseti(date = new Date(+date), step == null ? 1 : Math.floor(step)), date;
    };

    interval.range = function (start, stop, step) {
      var range = [],
          previous;
      start = interval.ceil(start);
      step = step == null ? 1 : Math.floor(step);
      if (!(start < stop) || !(step > 0)) return range; // also handles Invalid Date

      do {
        range.push(previous = new Date(+start)), offseti(start, step), floori(start);
      } while (previous < start && start < stop);

      return range;
    };

    interval.filter = function (test) {
      return newInterval(function (date) {
        if (date >= date) while (floori(date), !test(date)) {
          date.setTime(date - 1);
        }
      }, function (date, step) {
        if (date >= date) {
          if (step < 0) while (++step <= 0) {
            while (offseti(date, -1), !test(date)) {} // eslint-disable-line no-empty

          } else while (--step >= 0) {
            while (offseti(date, +1), !test(date)) {} // eslint-disable-line no-empty

          }
        }
      });
    };

    if (count) {
      interval.count = function (start, end) {
        t0$1.setTime(+start), t1$1.setTime(+end);
        floori(t0$1), floori(t1$1);
        return Math.floor(count(t0$1, t1$1));
      };

      interval.every = function (step) {
        step = Math.floor(step);
        return !isFinite(step) || !(step > 0) ? null : !(step > 1) ? interval : interval.filter(field ? function (d) {
          return field(d) % step === 0;
        } : function (d) {
          return interval.count(0, d) % step === 0;
        });
      };
    }

    return interval;
  }

  var millisecond = newInterval(function () {// noop
  }, function (date, step) {
    date.setTime(+date + step);
  }, function (start, end) {
    return end - start;
  }); // An optimized implementation for this simple case.

  millisecond.every = function (k) {
    k = Math.floor(k);
    if (!isFinite(k) || !(k > 0)) return null;
    if (!(k > 1)) return millisecond;
    return newInterval(function (date) {
      date.setTime(Math.floor(date / k) * k);
    }, function (date, step) {
      date.setTime(+date + step * k);
    }, function (start, end) {
      return (end - start) / k;
    });
  };
  var milliseconds = millisecond.range;

  var durationSecond = 1e3;
  var durationMinute = 6e4;
  var durationHour = 36e5;
  var durationDay = 864e5;
  var durationWeek = 6048e5;

  var second = newInterval(function (date) {
    date.setTime(date - date.getMilliseconds());
  }, function (date, step) {
    date.setTime(+date + step * durationSecond);
  }, function (start, end) {
    return (end - start) / durationSecond;
  }, function (date) {
    return date.getUTCSeconds();
  });
  var seconds = second.range;

  var minute = newInterval(function (date) {
    date.setTime(date - date.getMilliseconds() - date.getSeconds() * durationSecond);
  }, function (date, step) {
    date.setTime(+date + step * durationMinute);
  }, function (start, end) {
    return (end - start) / durationMinute;
  }, function (date) {
    return date.getMinutes();
  });
  var minutes = minute.range;

  var hour = newInterval(function (date) {
    date.setTime(date - date.getMilliseconds() - date.getSeconds() * durationSecond - date.getMinutes() * durationMinute);
  }, function (date, step) {
    date.setTime(+date + step * durationHour);
  }, function (start, end) {
    return (end - start) / durationHour;
  }, function (date) {
    return date.getHours();
  });
  var hours = hour.range;

  var day = newInterval(function (date) {
    date.setHours(0, 0, 0, 0);
  }, function (date, step) {
    date.setDate(date.getDate() + step);
  }, function (start, end) {
    return (end - start - (end.getTimezoneOffset() - start.getTimezoneOffset()) * durationMinute) / durationDay;
  }, function (date) {
    return date.getDate() - 1;
  });
  var days = day.range;

  function weekday(i) {
    return newInterval(function (date) {
      date.setDate(date.getDate() - (date.getDay() + 7 - i) % 7);
      date.setHours(0, 0, 0, 0);
    }, function (date, step) {
      date.setDate(date.getDate() + step * 7);
    }, function (start, end) {
      return (end - start - (end.getTimezoneOffset() - start.getTimezoneOffset()) * durationMinute) / durationWeek;
    });
  }

  var sunday = weekday(0);
  var monday = weekday(1);
  var tuesday = weekday(2);
  var wednesday = weekday(3);
  var thursday = weekday(4);
  var friday = weekday(5);
  var saturday = weekday(6);
  var sundays = sunday.range;
  var mondays = monday.range;
  var tuesdays = tuesday.range;
  var wednesdays = wednesday.range;
  var thursdays = thursday.range;
  var fridays = friday.range;
  var saturdays = saturday.range;

  var month = newInterval(function (date) {
    date.setDate(1);
    date.setHours(0, 0, 0, 0);
  }, function (date, step) {
    date.setMonth(date.getMonth() + step);
  }, function (start, end) {
    return end.getMonth() - start.getMonth() + (end.getFullYear() - start.getFullYear()) * 12;
  }, function (date) {
    return date.getMonth();
  });
  var months = month.range;

  var year = newInterval(function (date) {
    date.setMonth(0, 1);
    date.setHours(0, 0, 0, 0);
  }, function (date, step) {
    date.setFullYear(date.getFullYear() + step);
  }, function (start, end) {
    return end.getFullYear() - start.getFullYear();
  }, function (date) {
    return date.getFullYear();
  }); // An optimized implementation for this simple case.

  year.every = function (k) {
    return !isFinite(k = Math.floor(k)) || !(k > 0) ? null : newInterval(function (date) {
      date.setFullYear(Math.floor(date.getFullYear() / k) * k);
      date.setMonth(0, 1);
      date.setHours(0, 0, 0, 0);
    }, function (date, step) {
      date.setFullYear(date.getFullYear() + step * k);
    });
  };
  var years = year.range;

  var utcMinute = newInterval(function (date) {
    date.setUTCSeconds(0, 0);
  }, function (date, step) {
    date.setTime(+date + step * durationMinute);
  }, function (start, end) {
    return (end - start) / durationMinute;
  }, function (date) {
    return date.getUTCMinutes();
  });
  var utcMinutes = utcMinute.range;

  var utcHour = newInterval(function (date) {
    date.setUTCMinutes(0, 0, 0);
  }, function (date, step) {
    date.setTime(+date + step * durationHour);
  }, function (start, end) {
    return (end - start) / durationHour;
  }, function (date) {
    return date.getUTCHours();
  });
  var utcHours = utcHour.range;

  var utcDay = newInterval(function (date) {
    date.setUTCHours(0, 0, 0, 0);
  }, function (date, step) {
    date.setUTCDate(date.getUTCDate() + step);
  }, function (start, end) {
    return (end - start) / durationDay;
  }, function (date) {
    return date.getUTCDate() - 1;
  });
  var utcDays = utcDay.range;

  function utcWeekday(i) {
    return newInterval(function (date) {
      date.setUTCDate(date.getUTCDate() - (date.getUTCDay() + 7 - i) % 7);
      date.setUTCHours(0, 0, 0, 0);
    }, function (date, step) {
      date.setUTCDate(date.getUTCDate() + step * 7);
    }, function (start, end) {
      return (end - start) / durationWeek;
    });
  }

  var utcSunday = utcWeekday(0);
  var utcMonday = utcWeekday(1);
  var utcTuesday = utcWeekday(2);
  var utcWednesday = utcWeekday(3);
  var utcThursday = utcWeekday(4);
  var utcFriday = utcWeekday(5);
  var utcSaturday = utcWeekday(6);
  var utcSundays = utcSunday.range;
  var utcMondays = utcMonday.range;
  var utcTuesdays = utcTuesday.range;
  var utcWednesdays = utcWednesday.range;
  var utcThursdays = utcThursday.range;
  var utcFridays = utcFriday.range;
  var utcSaturdays = utcSaturday.range;

  var utcMonth = newInterval(function (date) {
    date.setUTCDate(1);
    date.setUTCHours(0, 0, 0, 0);
  }, function (date, step) {
    date.setUTCMonth(date.getUTCMonth() + step);
  }, function (start, end) {
    return end.getUTCMonth() - start.getUTCMonth() + (end.getUTCFullYear() - start.getUTCFullYear()) * 12;
  }, function (date) {
    return date.getUTCMonth();
  });
  var utcMonths = utcMonth.range;

  var utcYear = newInterval(function (date) {
    date.setUTCMonth(0, 1);
    date.setUTCHours(0, 0, 0, 0);
  }, function (date, step) {
    date.setUTCFullYear(date.getUTCFullYear() + step);
  }, function (start, end) {
    return end.getUTCFullYear() - start.getUTCFullYear();
  }, function (date) {
    return date.getUTCFullYear();
  }); // An optimized implementation for this simple case.

  utcYear.every = function (k) {
    return !isFinite(k = Math.floor(k)) || !(k > 0) ? null : newInterval(function (date) {
      date.setUTCFullYear(Math.floor(date.getUTCFullYear() / k) * k);
      date.setUTCMonth(0, 1);
      date.setUTCHours(0, 0, 0, 0);
    }, function (date, step) {
      date.setUTCFullYear(date.getUTCFullYear() + step * k);
    });
  };
  var utcYears = utcYear.range;

  function localDate(d) {
    if (0 <= d.y && d.y < 100) {
      var date = new Date(-1, d.m, d.d, d.H, d.M, d.S, d.L);
      date.setFullYear(d.y);
      return date;
    }

    return new Date(d.y, d.m, d.d, d.H, d.M, d.S, d.L);
  }

  function utcDate(d) {
    if (0 <= d.y && d.y < 100) {
      var date = new Date(Date.UTC(-1, d.m, d.d, d.H, d.M, d.S, d.L));
      date.setUTCFullYear(d.y);
      return date;
    }

    return new Date(Date.UTC(d.y, d.m, d.d, d.H, d.M, d.S, d.L));
  }

  function newYear(y) {
    return {
      y: y,
      m: 0,
      d: 1,
      H: 0,
      M: 0,
      S: 0,
      L: 0
    };
  }

  function formatLocale$1(locale) {
    var locale_dateTime = locale.dateTime,
        locale_date = locale.date,
        locale_time = locale.time,
        locale_periods = locale.periods,
        locale_weekdays = locale.days,
        locale_shortWeekdays = locale.shortDays,
        locale_months = locale.months,
        locale_shortMonths = locale.shortMonths;
    var periodRe = formatRe(locale_periods),
        periodLookup = formatLookup(locale_periods),
        weekdayRe = formatRe(locale_weekdays),
        weekdayLookup = formatLookup(locale_weekdays),
        shortWeekdayRe = formatRe(locale_shortWeekdays),
        shortWeekdayLookup = formatLookup(locale_shortWeekdays),
        monthRe = formatRe(locale_months),
        monthLookup = formatLookup(locale_months),
        shortMonthRe = formatRe(locale_shortMonths),
        shortMonthLookup = formatLookup(locale_shortMonths);
    var formats = {
      "a": formatShortWeekday,
      "A": formatWeekday,
      "b": formatShortMonth,
      "B": formatMonth,
      "c": null,
      "d": formatDayOfMonth,
      "e": formatDayOfMonth,
      "f": formatMicroseconds,
      "H": formatHour24,
      "I": formatHour12,
      "j": formatDayOfYear,
      "L": formatMilliseconds,
      "m": formatMonthNumber,
      "M": formatMinutes,
      "p": formatPeriod,
      "Q": formatUnixTimestamp,
      "s": formatUnixTimestampSeconds,
      "S": formatSeconds,
      "u": formatWeekdayNumberMonday,
      "U": formatWeekNumberSunday,
      "V": formatWeekNumberISO,
      "w": formatWeekdayNumberSunday,
      "W": formatWeekNumberMonday,
      "x": null,
      "X": null,
      "y": formatYear$1,
      "Y": formatFullYear,
      "Z": formatZone,
      "%": formatLiteralPercent
    };
    var utcFormats = {
      "a": formatUTCShortWeekday,
      "A": formatUTCWeekday,
      "b": formatUTCShortMonth,
      "B": formatUTCMonth,
      "c": null,
      "d": formatUTCDayOfMonth,
      "e": formatUTCDayOfMonth,
      "f": formatUTCMicroseconds,
      "H": formatUTCHour24,
      "I": formatUTCHour12,
      "j": formatUTCDayOfYear,
      "L": formatUTCMilliseconds,
      "m": formatUTCMonthNumber,
      "M": formatUTCMinutes,
      "p": formatUTCPeriod,
      "Q": formatUnixTimestamp,
      "s": formatUnixTimestampSeconds,
      "S": formatUTCSeconds,
      "u": formatUTCWeekdayNumberMonday,
      "U": formatUTCWeekNumberSunday,
      "V": formatUTCWeekNumberISO,
      "w": formatUTCWeekdayNumberSunday,
      "W": formatUTCWeekNumberMonday,
      "x": null,
      "X": null,
      "y": formatUTCYear,
      "Y": formatUTCFullYear,
      "Z": formatUTCZone,
      "%": formatLiteralPercent
    };
    var parses = {
      "a": parseShortWeekday,
      "A": parseWeekday,
      "b": parseShortMonth,
      "B": parseMonth,
      "c": parseLocaleDateTime,
      "d": parseDayOfMonth,
      "e": parseDayOfMonth,
      "f": parseMicroseconds,
      "H": parseHour24,
      "I": parseHour24,
      "j": parseDayOfYear,
      "L": parseMilliseconds,
      "m": parseMonthNumber,
      "M": parseMinutes,
      "p": parsePeriod,
      "Q": parseUnixTimestamp,
      "s": parseUnixTimestampSeconds,
      "S": parseSeconds,
      "u": parseWeekdayNumberMonday,
      "U": parseWeekNumberSunday,
      "V": parseWeekNumberISO,
      "w": parseWeekdayNumberSunday,
      "W": parseWeekNumberMonday,
      "x": parseLocaleDate,
      "X": parseLocaleTime,
      "y": parseYear,
      "Y": parseFullYear,
      "Z": parseZone,
      "%": parseLiteralPercent
    }; // These recursive directive definitions must be deferred.

    formats.x = newFormat(locale_date, formats);
    formats.X = newFormat(locale_time, formats);
    formats.c = newFormat(locale_dateTime, formats);
    utcFormats.x = newFormat(locale_date, utcFormats);
    utcFormats.X = newFormat(locale_time, utcFormats);
    utcFormats.c = newFormat(locale_dateTime, utcFormats);

    function newFormat(specifier, formats) {
      return function (date) {
        var string = [],
            i = -1,
            j = 0,
            n = specifier.length,
            c,
            pad,
            format;
        if (!(date instanceof Date)) date = new Date(+date);

        while (++i < n) {
          if (specifier.charCodeAt(i) === 37) {
            string.push(specifier.slice(j, i));
            if ((pad = pads[c = specifier.charAt(++i)]) != null) c = specifier.charAt(++i);else pad = c === "e" ? " " : "0";
            if (format = formats[c]) c = format(date, pad);
            string.push(c);
            j = i + 1;
          }
        }

        string.push(specifier.slice(j, i));
        return string.join("");
      };
    }

    function newParse(specifier, newDate) {
      return function (string) {
        var d = newYear(1900),
            i = parseSpecifier(d, specifier, string += "", 0),
            week,
            day$$1;
        if (i != string.length) return null; // If a UNIX timestamp is specified, return it.

        if ("Q" in d) return new Date(d.Q); // The am-pm flag is 0 for AM, and 1 for PM.

        if ("p" in d) d.H = d.H % 12 + d.p * 12; // Convert day-of-week and week-of-year to day-of-year.

        if ("V" in d) {
          if (d.V < 1 || d.V > 53) return null;
          if (!("w" in d)) d.w = 1;

          if ("Z" in d) {
            week = utcDate(newYear(d.y)), day$$1 = week.getUTCDay();
            week = day$$1 > 4 || day$$1 === 0 ? utcMonday.ceil(week) : utcMonday(week);
            week = utcDay.offset(week, (d.V - 1) * 7);
            d.y = week.getUTCFullYear();
            d.m = week.getUTCMonth();
            d.d = week.getUTCDate() + (d.w + 6) % 7;
          } else {
            week = newDate(newYear(d.y)), day$$1 = week.getDay();
            week = day$$1 > 4 || day$$1 === 0 ? monday.ceil(week) : monday(week);
            week = day.offset(week, (d.V - 1) * 7);
            d.y = week.getFullYear();
            d.m = week.getMonth();
            d.d = week.getDate() + (d.w + 6) % 7;
          }
        } else if ("W" in d || "U" in d) {
          if (!("w" in d)) d.w = "u" in d ? d.u % 7 : "W" in d ? 1 : 0;
          day$$1 = "Z" in d ? utcDate(newYear(d.y)).getUTCDay() : newDate(newYear(d.y)).getDay();
          d.m = 0;
          d.d = "W" in d ? (d.w + 6) % 7 + d.W * 7 - (day$$1 + 5) % 7 : d.w + d.U * 7 - (day$$1 + 6) % 7;
        } // If a time zone is specified, all fields are interpreted as UTC and then
        // offset according to the specified time zone.


        if ("Z" in d) {
          d.H += d.Z / 100 | 0;
          d.M += d.Z % 100;
          return utcDate(d);
        } // Otherwise, all fields are in local time.


        return newDate(d);
      };
    }

    function parseSpecifier(d, specifier, string, j) {
      var i = 0,
          n = specifier.length,
          m = string.length,
          c,
          parse;

      while (i < n) {
        if (j >= m) return -1;
        c = specifier.charCodeAt(i++);

        if (c === 37) {
          c = specifier.charAt(i++);
          parse = parses[c in pads ? specifier.charAt(i++) : c];
          if (!parse || (j = parse(d, string, j)) < 0) return -1;
        } else if (c != string.charCodeAt(j++)) {
          return -1;
        }
      }

      return j;
    }

    function parsePeriod(d, string, i) {
      var n = periodRe.exec(string.slice(i));
      return n ? (d.p = periodLookup[n[0].toLowerCase()], i + n[0].length) : -1;
    }

    function parseShortWeekday(d, string, i) {
      var n = shortWeekdayRe.exec(string.slice(i));
      return n ? (d.w = shortWeekdayLookup[n[0].toLowerCase()], i + n[0].length) : -1;
    }

    function parseWeekday(d, string, i) {
      var n = weekdayRe.exec(string.slice(i));
      return n ? (d.w = weekdayLookup[n[0].toLowerCase()], i + n[0].length) : -1;
    }

    function parseShortMonth(d, string, i) {
      var n = shortMonthRe.exec(string.slice(i));
      return n ? (d.m = shortMonthLookup[n[0].toLowerCase()], i + n[0].length) : -1;
    }

    function parseMonth(d, string, i) {
      var n = monthRe.exec(string.slice(i));
      return n ? (d.m = monthLookup[n[0].toLowerCase()], i + n[0].length) : -1;
    }

    function parseLocaleDateTime(d, string, i) {
      return parseSpecifier(d, locale_dateTime, string, i);
    }

    function parseLocaleDate(d, string, i) {
      return parseSpecifier(d, locale_date, string, i);
    }

    function parseLocaleTime(d, string, i) {
      return parseSpecifier(d, locale_time, string, i);
    }

    function formatShortWeekday(d) {
      return locale_shortWeekdays[d.getDay()];
    }

    function formatWeekday(d) {
      return locale_weekdays[d.getDay()];
    }

    function formatShortMonth(d) {
      return locale_shortMonths[d.getMonth()];
    }

    function formatMonth(d) {
      return locale_months[d.getMonth()];
    }

    function formatPeriod(d) {
      return locale_periods[+(d.getHours() >= 12)];
    }

    function formatUTCShortWeekday(d) {
      return locale_shortWeekdays[d.getUTCDay()];
    }

    function formatUTCWeekday(d) {
      return locale_weekdays[d.getUTCDay()];
    }

    function formatUTCShortMonth(d) {
      return locale_shortMonths[d.getUTCMonth()];
    }

    function formatUTCMonth(d) {
      return locale_months[d.getUTCMonth()];
    }

    function formatUTCPeriod(d) {
      return locale_periods[+(d.getUTCHours() >= 12)];
    }

    return {
      format: function format(specifier) {
        var f = newFormat(specifier += "", formats);

        f.toString = function () {
          return specifier;
        };

        return f;
      },
      parse: function parse(specifier) {
        var p = newParse(specifier += "", localDate);

        p.toString = function () {
          return specifier;
        };

        return p;
      },
      utcFormat: function utcFormat(specifier) {
        var f = newFormat(specifier += "", utcFormats);

        f.toString = function () {
          return specifier;
        };

        return f;
      },
      utcParse: function utcParse(specifier) {
        var p = newParse(specifier, utcDate);

        p.toString = function () {
          return specifier;
        };

        return p;
      }
    };
  }
  var pads = {
    "-": "",
    "_": " ",
    "0": "0"
  },
      numberRe = /^\s*\d+/,
      // note: ignores next directive
  percentRe = /^%/,
      requoteRe = /[\\^$*+?|[\]().{}]/g;

  function pad$1(value, fill, width) {
    var sign = value < 0 ? "-" : "",
        string = (sign ? -value : value) + "",
        length = string.length;
    return sign + (length < width ? new Array(width - length + 1).join(fill) + string : string);
  }

  function requote(s) {
    return s.replace(requoteRe, "\\$&");
  }

  function formatRe(names) {
    return new RegExp("^(?:" + names.map(requote).join("|") + ")", "i");
  }

  function formatLookup(names) {
    var map = {},
        i = -1,
        n = names.length;

    while (++i < n) {
      map[names[i].toLowerCase()] = i;
    }

    return map;
  }

  function parseWeekdayNumberSunday(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 1));
    return n ? (d.w = +n[0], i + n[0].length) : -1;
  }

  function parseWeekdayNumberMonday(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 1));
    return n ? (d.u = +n[0], i + n[0].length) : -1;
  }

  function parseWeekNumberSunday(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.U = +n[0], i + n[0].length) : -1;
  }

  function parseWeekNumberISO(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.V = +n[0], i + n[0].length) : -1;
  }

  function parseWeekNumberMonday(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.W = +n[0], i + n[0].length) : -1;
  }

  function parseFullYear(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 4));
    return n ? (d.y = +n[0], i + n[0].length) : -1;
  }

  function parseYear(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.y = +n[0] + (+n[0] > 68 ? 1900 : 2000), i + n[0].length) : -1;
  }

  function parseZone(d, string, i) {
    var n = /^(Z)|([+-]\d\d)(?::?(\d\d))?/.exec(string.slice(i, i + 6));
    return n ? (d.Z = n[1] ? 0 : -(n[2] + (n[3] || "00")), i + n[0].length) : -1;
  }

  function parseMonthNumber(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.m = n[0] - 1, i + n[0].length) : -1;
  }

  function parseDayOfMonth(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.d = +n[0], i + n[0].length) : -1;
  }

  function parseDayOfYear(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 3));
    return n ? (d.m = 0, d.d = +n[0], i + n[0].length) : -1;
  }

  function parseHour24(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.H = +n[0], i + n[0].length) : -1;
  }

  function parseMinutes(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.M = +n[0], i + n[0].length) : -1;
  }

  function parseSeconds(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 2));
    return n ? (d.S = +n[0], i + n[0].length) : -1;
  }

  function parseMilliseconds(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 3));
    return n ? (d.L = +n[0], i + n[0].length) : -1;
  }

  function parseMicroseconds(d, string, i) {
    var n = numberRe.exec(string.slice(i, i + 6));
    return n ? (d.L = Math.floor(n[0] / 1000), i + n[0].length) : -1;
  }

  function parseLiteralPercent(d, string, i) {
    var n = percentRe.exec(string.slice(i, i + 1));
    return n ? i + n[0].length : -1;
  }

  function parseUnixTimestamp(d, string, i) {
    var n = numberRe.exec(string.slice(i));
    return n ? (d.Q = +n[0], i + n[0].length) : -1;
  }

  function parseUnixTimestampSeconds(d, string, i) {
    var n = numberRe.exec(string.slice(i));
    return n ? (d.Q = +n[0] * 1000, i + n[0].length) : -1;
  }

  function formatDayOfMonth(d, p) {
    return pad$1(d.getDate(), p, 2);
  }

  function formatHour24(d, p) {
    return pad$1(d.getHours(), p, 2);
  }

  function formatHour12(d, p) {
    return pad$1(d.getHours() % 12 || 12, p, 2);
  }

  function formatDayOfYear(d, p) {
    return pad$1(1 + day.count(year(d), d), p, 3);
  }

  function formatMilliseconds(d, p) {
    return pad$1(d.getMilliseconds(), p, 3);
  }

  function formatMicroseconds(d, p) {
    return formatMilliseconds(d, p) + "000";
  }

  function formatMonthNumber(d, p) {
    return pad$1(d.getMonth() + 1, p, 2);
  }

  function formatMinutes(d, p) {
    return pad$1(d.getMinutes(), p, 2);
  }

  function formatSeconds(d, p) {
    return pad$1(d.getSeconds(), p, 2);
  }

  function formatWeekdayNumberMonday(d) {
    var day$$1 = d.getDay();
    return day$$1 === 0 ? 7 : day$$1;
  }

  function formatWeekNumberSunday(d, p) {
    return pad$1(sunday.count(year(d), d), p, 2);
  }

  function formatWeekNumberISO(d, p) {
    var day$$1 = d.getDay();
    d = day$$1 >= 4 || day$$1 === 0 ? thursday(d) : thursday.ceil(d);
    return pad$1(thursday.count(year(d), d) + (year(d).getDay() === 4), p, 2);
  }

  function formatWeekdayNumberSunday(d) {
    return d.getDay();
  }

  function formatWeekNumberMonday(d, p) {
    return pad$1(monday.count(year(d), d), p, 2);
  }

  function formatYear$1(d, p) {
    return pad$1(d.getFullYear() % 100, p, 2);
  }

  function formatFullYear(d, p) {
    return pad$1(d.getFullYear() % 10000, p, 4);
  }

  function formatZone(d) {
    var z = d.getTimezoneOffset();
    return (z > 0 ? "-" : (z *= -1, "+")) + pad$1(z / 60 | 0, "0", 2) + pad$1(z % 60, "0", 2);
  }

  function formatUTCDayOfMonth(d, p) {
    return pad$1(d.getUTCDate(), p, 2);
  }

  function formatUTCHour24(d, p) {
    return pad$1(d.getUTCHours(), p, 2);
  }

  function formatUTCHour12(d, p) {
    return pad$1(d.getUTCHours() % 12 || 12, p, 2);
  }

  function formatUTCDayOfYear(d, p) {
    return pad$1(1 + utcDay.count(utcYear(d), d), p, 3);
  }

  function formatUTCMilliseconds(d, p) {
    return pad$1(d.getUTCMilliseconds(), p, 3);
  }

  function formatUTCMicroseconds(d, p) {
    return formatUTCMilliseconds(d, p) + "000";
  }

  function formatUTCMonthNumber(d, p) {
    return pad$1(d.getUTCMonth() + 1, p, 2);
  }

  function formatUTCMinutes(d, p) {
    return pad$1(d.getUTCMinutes(), p, 2);
  }

  function formatUTCSeconds(d, p) {
    return pad$1(d.getUTCSeconds(), p, 2);
  }

  function formatUTCWeekdayNumberMonday(d) {
    var dow = d.getUTCDay();
    return dow === 0 ? 7 : dow;
  }

  function formatUTCWeekNumberSunday(d, p) {
    return pad$1(utcSunday.count(utcYear(d), d), p, 2);
  }

  function formatUTCWeekNumberISO(d, p) {
    var day$$1 = d.getUTCDay();
    d = day$$1 >= 4 || day$$1 === 0 ? utcThursday(d) : utcThursday.ceil(d);
    return pad$1(utcThursday.count(utcYear(d), d) + (utcYear(d).getUTCDay() === 4), p, 2);
  }

  function formatUTCWeekdayNumberSunday(d) {
    return d.getUTCDay();
  }

  function formatUTCWeekNumberMonday(d, p) {
    return pad$1(utcMonday.count(utcYear(d), d), p, 2);
  }

  function formatUTCYear(d, p) {
    return pad$1(d.getUTCFullYear() % 100, p, 2);
  }

  function formatUTCFullYear(d, p) {
    return pad$1(d.getUTCFullYear() % 10000, p, 4);
  }

  function formatUTCZone() {
    return "+0000";
  }

  function formatLiteralPercent() {
    return "%";
  }

  function formatUnixTimestamp(d) {
    return +d;
  }

  function formatUnixTimestampSeconds(d) {
    return Math.floor(+d / 1000);
  }

  var locale$1;
  defaultLocale$1({
    dateTime: "%x, %X",
    date: "%-m/%-d/%Y",
    time: "%-I:%M:%S %p",
    periods: ["AM", "PM"],
    days: ["Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"],
    shortDays: ["Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"],
    months: ["January", "February", "March", "April", "May", "June", "July", "August", "September", "October", "November", "December"],
    shortMonths: ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"]
  });
  function defaultLocale$1(definition) {
    locale$1 = formatLocale$1(definition);
    exports.timeFormat = locale$1.format;
    exports.timeParse = locale$1.parse;
    exports.utcFormat = locale$1.utcFormat;
    exports.utcParse = locale$1.utcParse;
    return locale$1;
  }

  var isoSpecifier = "%Y-%m-%dT%H:%M:%S.%LZ";

  function formatIsoNative(date) {
    return date.toISOString();
  }

  var formatIso = Date.prototype.toISOString ? formatIsoNative : exports.utcFormat(isoSpecifier);

  function parseIsoNative(string) {
    var date = new Date(string);
    return isNaN(date) ? null : date;
  }

  var parseIso = +new Date("2000-01-01T00:00:00.000Z") ? parseIsoNative : exports.utcParse(isoSpecifier);

  var durationSecond$1 = 1000,
      durationMinute$1 = durationSecond$1 * 60,
      durationHour$1 = durationMinute$1 * 60,
      durationDay$1 = durationHour$1 * 24,
      durationWeek$1 = durationDay$1 * 7,
      durationMonth = durationDay$1 * 30,
      durationYear = durationDay$1 * 365;

  function date$1(t) {
    return new Date(t);
  }

  function number$3(t) {
    return t instanceof Date ? +t : +new Date(+t);
  }

  function calendar(year$$1, month$$1, week, day$$1, hour$$1, minute$$1, second$$1, millisecond$$1, format) {
    var scale = continuous(identity$6, identity$6),
        invert = scale.invert,
        domain = scale.domain;
    var formatMillisecond = format(".%L"),
        formatSecond = format(":%S"),
        formatMinute = format("%I:%M"),
        formatHour = format("%I %p"),
        formatDay = format("%a %d"),
        formatWeek = format("%b %d"),
        formatMonth = format("%B"),
        formatYear = format("%Y");
    var tickIntervals = [[second$$1, 1, durationSecond$1], [second$$1, 5, 5 * durationSecond$1], [second$$1, 15, 15 * durationSecond$1], [second$$1, 30, 30 * durationSecond$1], [minute$$1, 1, durationMinute$1], [minute$$1, 5, 5 * durationMinute$1], [minute$$1, 15, 15 * durationMinute$1], [minute$$1, 30, 30 * durationMinute$1], [hour$$1, 1, durationHour$1], [hour$$1, 3, 3 * durationHour$1], [hour$$1, 6, 6 * durationHour$1], [hour$$1, 12, 12 * durationHour$1], [day$$1, 1, durationDay$1], [day$$1, 2, 2 * durationDay$1], [week, 1, durationWeek$1], [month$$1, 1, durationMonth], [month$$1, 3, 3 * durationMonth], [year$$1, 1, durationYear]];

    function tickFormat(date) {
      return (second$$1(date) < date ? formatMillisecond : minute$$1(date) < date ? formatSecond : hour$$1(date) < date ? formatMinute : day$$1(date) < date ? formatHour : month$$1(date) < date ? week(date) < date ? formatDay : formatWeek : year$$1(date) < date ? formatMonth : formatYear)(date);
    }

    function tickInterval(interval, start, stop, step) {
      if (interval == null) interval = 10; // If a desired tick count is specified, pick a reasonable tick interval
      // based on the extent of the domain and a rough estimate of tick size.
      // Otherwise, assume interval is already a time interval and use it.

      if (typeof interval === "number") {
        var target = Math.abs(stop - start) / interval,
            i = bisector(function (i) {
          return i[2];
        }).right(tickIntervals, target);

        if (i === tickIntervals.length) {
          step = tickStep(start / durationYear, stop / durationYear, interval);
          interval = year$$1;
        } else if (i) {
          i = tickIntervals[target / tickIntervals[i - 1][2] < tickIntervals[i][2] / target ? i - 1 : i];
          step = i[1];
          interval = i[0];
        } else {
          step = Math.max(tickStep(start, stop, interval), 1);
          interval = millisecond$$1;
        }
      }

      return step == null ? interval : interval.every(step);
    }

    scale.invert = function (y) {
      return new Date(invert(y));
    };

    scale.domain = function (_) {
      return arguments.length ? domain(map$2.call(_, number$3)) : domain().map(date$1);
    };

    scale.ticks = function (interval, step) {
      var d = domain(),
          t0 = d[0],
          t1 = d[d.length - 1],
          r = t1 < t0,
          t;
      if (r) t = t0, t0 = t1, t1 = t;
      t = tickInterval(interval, t0, t1, step);
      t = t ? t.range(t0, t1 + 1) : []; // inclusive stop

      return r ? t.reverse() : t;
    };

    scale.tickFormat = function (count, specifier) {
      return specifier == null ? tickFormat : format(specifier);
    };

    scale.nice = function (interval, step) {
      var d = domain();
      return (interval = tickInterval(interval, d[0], d[d.length - 1], step)) ? domain(nice(d, interval)) : scale;
    };

    scale.copy = function () {
      return copy(scale, calendar(year$$1, month$$1, week, day$$1, hour$$1, minute$$1, second$$1, millisecond$$1, format));
    };

    return scale;
  }
  function time () {
    return initRange.apply(calendar(year, month, sunday, day, hour, minute, second, millisecond, exports.timeFormat).domain([new Date(2000, 0, 1), new Date(2000, 0, 2)]), arguments);
  }

  function utcTime () {
    return initRange.apply(calendar(utcYear, utcMonth, utcSunday, utcDay, utcHour, utcMinute, second, millisecond, exports.utcFormat).domain([Date.UTC(2000, 0, 1), Date.UTC(2000, 0, 2)]), arguments);
  }

  function transformer$2() {
    var x0 = 0,
        x1 = 1,
        t0,
        t1,
        k10,
        transform,
        interpolator = identity$6,
        clamp = false,
        unknown;

    function scale(x) {
      return isNaN(x = +x) ? unknown : interpolator(k10 === 0 ? 0.5 : (x = (transform(x) - t0) * k10, clamp ? Math.max(0, Math.min(1, x)) : x));
    }

    scale.domain = function (_) {
      return arguments.length ? (t0 = transform(x0 = +_[0]), t1 = transform(x1 = +_[1]), k10 = t0 === t1 ? 0 : 1 / (t1 - t0), scale) : [x0, x1];
    };

    scale.clamp = function (_) {
      return arguments.length ? (clamp = !!_, scale) : clamp;
    };

    scale.interpolator = function (_) {
      return arguments.length ? (interpolator = _, scale) : interpolator;
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    return function (t) {
      transform = t, t0 = t(x0), t1 = t(x1), k10 = t0 === t1 ? 0 : 1 / (t1 - t0);
      return scale;
    };
  }

  function copy$1(source, target) {
    return target.domain(source.domain()).interpolator(source.interpolator()).clamp(source.clamp()).unknown(source.unknown());
  }
  function sequential() {
    var scale = linearish(transformer$2()(identity$6));

    scale.copy = function () {
      return copy$1(scale, sequential());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function sequentialLog() {
    var scale = loggish(transformer$2()).domain([1, 10]);

    scale.copy = function () {
      return copy$1(scale, sequentialLog()).base(scale.base());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function sequentialSymlog() {
    var scale = symlogish(transformer$2());

    scale.copy = function () {
      return copy$1(scale, sequentialSymlog()).constant(scale.constant());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function sequentialPow() {
    var scale = powish(transformer$2());

    scale.copy = function () {
      return copy$1(scale, sequentialPow()).exponent(scale.exponent());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function sequentialSqrt() {
    return sequentialPow.apply(null, arguments).exponent(0.5);
  }

  function sequentialQuantile() {
    var domain = [],
        interpolator = identity$6;

    function scale(x) {
      if (!isNaN(x = +x)) return interpolator((bisectRight(domain, x) - 1) / (domain.length - 1));
    }

    scale.domain = function (_) {
      if (!arguments.length) return domain.slice();
      domain = [];

      for (var i = 0, n = _.length, d; i < n; ++i) {
        if (d = _[i], d != null && !isNaN(d = +d)) domain.push(d);
      }

      domain.sort(ascending);
      return scale;
    };

    scale.interpolator = function (_) {
      return arguments.length ? (interpolator = _, scale) : interpolator;
    };

    scale.copy = function () {
      return sequentialQuantile(interpolator).domain(domain);
    };

    return initInterpolator.apply(scale, arguments);
  }

  function transformer$3() {
    var x0 = 0,
        x1 = 0.5,
        x2 = 1,
        t0,
        t1,
        t2,
        k10,
        k21,
        interpolator = identity$6,
        transform,
        clamp = false,
        unknown;

    function scale(x) {
      return isNaN(x = +x) ? unknown : (x = 0.5 + ((x = +transform(x)) - t1) * (x < t1 ? k10 : k21), interpolator(clamp ? Math.max(0, Math.min(1, x)) : x));
    }

    scale.domain = function (_) {
      return arguments.length ? (t0 = transform(x0 = +_[0]), t1 = transform(x1 = +_[1]), t2 = transform(x2 = +_[2]), k10 = t0 === t1 ? 0 : 0.5 / (t1 - t0), k21 = t1 === t2 ? 0 : 0.5 / (t2 - t1), scale) : [x0, x1, x2];
    };

    scale.clamp = function (_) {
      return arguments.length ? (clamp = !!_, scale) : clamp;
    };

    scale.interpolator = function (_) {
      return arguments.length ? (interpolator = _, scale) : interpolator;
    };

    scale.unknown = function (_) {
      return arguments.length ? (unknown = _, scale) : unknown;
    };

    return function (t) {
      transform = t, t0 = t(x0), t1 = t(x1), t2 = t(x2), k10 = t0 === t1 ? 0 : 0.5 / (t1 - t0), k21 = t1 === t2 ? 0 : 0.5 / (t2 - t1);
      return scale;
    };
  }

  function diverging() {
    var scale = linearish(transformer$3()(identity$6));

    scale.copy = function () {
      return copy$1(scale, diverging());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function divergingLog() {
    var scale = loggish(transformer$3()).domain([0.1, 1, 10]);

    scale.copy = function () {
      return copy$1(scale, divergingLog()).base(scale.base());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function divergingSymlog() {
    var scale = symlogish(transformer$3());

    scale.copy = function () {
      return copy$1(scale, divergingSymlog()).constant(scale.constant());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function divergingPow() {
    var scale = powish(transformer$3());

    scale.copy = function () {
      return copy$1(scale, divergingPow()).exponent(scale.exponent());
    };

    return initInterpolator.apply(scale, arguments);
  }
  function divergingSqrt() {
    return divergingPow.apply(null, arguments).exponent(0.5);
  }

  function colors (specifier) {
    var n = specifier.length / 6 | 0,
        colors = new Array(n),
        i = 0;

    while (i < n) {
      colors[i] = "#" + specifier.slice(i * 6, ++i * 6);
    }

    return colors;
  }

  var category10 = colors("1f77b4ff7f0e2ca02cd627289467bd8c564be377c27f7f7fbcbd2217becf");

  var Accent = colors("7fc97fbeaed4fdc086ffff99386cb0f0027fbf5b17666666");

  var Dark2 = colors("1b9e77d95f027570b3e7298a66a61ee6ab02a6761d666666");

  var Paired = colors("a6cee31f78b4b2df8a33a02cfb9a99e31a1cfdbf6fff7f00cab2d66a3d9affff99b15928");

  var Pastel1 = colors("fbb4aeb3cde3ccebc5decbe4fed9a6ffffcce5d8bdfddaecf2f2f2");

  var Pastel2 = colors("b3e2cdfdcdaccbd5e8f4cae4e6f5c9fff2aef1e2cccccccc");

  var Set1 = colors("e41a1c377eb84daf4a984ea3ff7f00ffff33a65628f781bf999999");

  var Set2 = colors("66c2a5fc8d628da0cbe78ac3a6d854ffd92fe5c494b3b3b3");

  var Set3 = colors("8dd3c7ffffb3bebadafb807280b1d3fdb462b3de69fccde5d9d9d9bc80bdccebc5ffed6f");

  function ramp (scheme) {
    return rgbBasis(scheme[scheme.length - 1]);
  }

  var scheme = new Array(3).concat("d8b365f5f5f55ab4ac", "a6611adfc27d80cdc1018571", "a6611adfc27df5f5f580cdc1018571", "8c510ad8b365f6e8c3c7eae55ab4ac01665e", "8c510ad8b365f6e8c3f5f5f5c7eae55ab4ac01665e", "8c510abf812ddfc27df6e8c3c7eae580cdc135978f01665e", "8c510abf812ddfc27df6e8c3f5f5f5c7eae580cdc135978f01665e", "5430058c510abf812ddfc27df6e8c3c7eae580cdc135978f01665e003c30", "5430058c510abf812ddfc27df6e8c3f5f5f5c7eae580cdc135978f01665e003c30").map(colors);
  var BrBG = ramp(scheme);

  var scheme$1 = new Array(3).concat("af8dc3f7f7f77fbf7b", "7b3294c2a5cfa6dba0008837", "7b3294c2a5cff7f7f7a6dba0008837", "762a83af8dc3e7d4e8d9f0d37fbf7b1b7837", "762a83af8dc3e7d4e8f7f7f7d9f0d37fbf7b1b7837", "762a839970abc2a5cfe7d4e8d9f0d3a6dba05aae611b7837", "762a839970abc2a5cfe7d4e8f7f7f7d9f0d3a6dba05aae611b7837", "40004b762a839970abc2a5cfe7d4e8d9f0d3a6dba05aae611b783700441b", "40004b762a839970abc2a5cfe7d4e8f7f7f7d9f0d3a6dba05aae611b783700441b").map(colors);
  var PRGn = ramp(scheme$1);

  var scheme$2 = new Array(3).concat("e9a3c9f7f7f7a1d76a", "d01c8bf1b6dab8e1864dac26", "d01c8bf1b6daf7f7f7b8e1864dac26", "c51b7de9a3c9fde0efe6f5d0a1d76a4d9221", "c51b7de9a3c9fde0eff7f7f7e6f5d0a1d76a4d9221", "c51b7dde77aef1b6dafde0efe6f5d0b8e1867fbc414d9221", "c51b7dde77aef1b6dafde0eff7f7f7e6f5d0b8e1867fbc414d9221", "8e0152c51b7dde77aef1b6dafde0efe6f5d0b8e1867fbc414d9221276419", "8e0152c51b7dde77aef1b6dafde0eff7f7f7e6f5d0b8e1867fbc414d9221276419").map(colors);
  var PiYG = ramp(scheme$2);

  var scheme$3 = new Array(3).concat("998ec3f7f7f7f1a340", "5e3c99b2abd2fdb863e66101", "5e3c99b2abd2f7f7f7fdb863e66101", "542788998ec3d8daebfee0b6f1a340b35806", "542788998ec3d8daebf7f7f7fee0b6f1a340b35806", "5427888073acb2abd2d8daebfee0b6fdb863e08214b35806", "5427888073acb2abd2d8daebf7f7f7fee0b6fdb863e08214b35806", "2d004b5427888073acb2abd2d8daebfee0b6fdb863e08214b358067f3b08", "2d004b5427888073acb2abd2d8daebf7f7f7fee0b6fdb863e08214b358067f3b08").map(colors);
  var PuOr = ramp(scheme$3);

  var scheme$4 = new Array(3).concat("ef8a62f7f7f767a9cf", "ca0020f4a58292c5de0571b0", "ca0020f4a582f7f7f792c5de0571b0", "b2182bef8a62fddbc7d1e5f067a9cf2166ac", "b2182bef8a62fddbc7f7f7f7d1e5f067a9cf2166ac", "b2182bd6604df4a582fddbc7d1e5f092c5de4393c32166ac", "b2182bd6604df4a582fddbc7f7f7f7d1e5f092c5de4393c32166ac", "67001fb2182bd6604df4a582fddbc7d1e5f092c5de4393c32166ac053061", "67001fb2182bd6604df4a582fddbc7f7f7f7d1e5f092c5de4393c32166ac053061").map(colors);
  var RdBu = ramp(scheme$4);

  var scheme$5 = new Array(3).concat("ef8a62ffffff999999", "ca0020f4a582bababa404040", "ca0020f4a582ffffffbababa404040", "b2182bef8a62fddbc7e0e0e09999994d4d4d", "b2182bef8a62fddbc7ffffffe0e0e09999994d4d4d", "b2182bd6604df4a582fddbc7e0e0e0bababa8787874d4d4d", "b2182bd6604df4a582fddbc7ffffffe0e0e0bababa8787874d4d4d", "67001fb2182bd6604df4a582fddbc7e0e0e0bababa8787874d4d4d1a1a1a", "67001fb2182bd6604df4a582fddbc7ffffffe0e0e0bababa8787874d4d4d1a1a1a").map(colors);
  var RdGy = ramp(scheme$5);

  var scheme$6 = new Array(3).concat("fc8d59ffffbf91bfdb", "d7191cfdae61abd9e92c7bb6", "d7191cfdae61ffffbfabd9e92c7bb6", "d73027fc8d59fee090e0f3f891bfdb4575b4", "d73027fc8d59fee090ffffbfe0f3f891bfdb4575b4", "d73027f46d43fdae61fee090e0f3f8abd9e974add14575b4", "d73027f46d43fdae61fee090ffffbfe0f3f8abd9e974add14575b4", "a50026d73027f46d43fdae61fee090e0f3f8abd9e974add14575b4313695", "a50026d73027f46d43fdae61fee090ffffbfe0f3f8abd9e974add14575b4313695").map(colors);
  var RdYlBu = ramp(scheme$6);

  var scheme$7 = new Array(3).concat("fc8d59ffffbf91cf60", "d7191cfdae61a6d96a1a9641", "d7191cfdae61ffffbfa6d96a1a9641", "d73027fc8d59fee08bd9ef8b91cf601a9850", "d73027fc8d59fee08bffffbfd9ef8b91cf601a9850", "d73027f46d43fdae61fee08bd9ef8ba6d96a66bd631a9850", "d73027f46d43fdae61fee08bffffbfd9ef8ba6d96a66bd631a9850", "a50026d73027f46d43fdae61fee08bd9ef8ba6d96a66bd631a9850006837", "a50026d73027f46d43fdae61fee08bffffbfd9ef8ba6d96a66bd631a9850006837").map(colors);
  var RdYlGn = ramp(scheme$7);

  var scheme$8 = new Array(3).concat("fc8d59ffffbf99d594", "d7191cfdae61abdda42b83ba", "d7191cfdae61ffffbfabdda42b83ba", "d53e4ffc8d59fee08be6f59899d5943288bd", "d53e4ffc8d59fee08bffffbfe6f59899d5943288bd", "d53e4ff46d43fdae61fee08be6f598abdda466c2a53288bd", "d53e4ff46d43fdae61fee08bffffbfe6f598abdda466c2a53288bd", "9e0142d53e4ff46d43fdae61fee08be6f598abdda466c2a53288bd5e4fa2", "9e0142d53e4ff46d43fdae61fee08bffffbfe6f598abdda466c2a53288bd5e4fa2").map(colors);
  var Spectral = ramp(scheme$8);

  var scheme$9 = new Array(3).concat("e5f5f999d8c92ca25f", "edf8fbb2e2e266c2a4238b45", "edf8fbb2e2e266c2a42ca25f006d2c", "edf8fbccece699d8c966c2a42ca25f006d2c", "edf8fbccece699d8c966c2a441ae76238b45005824", "f7fcfde5f5f9ccece699d8c966c2a441ae76238b45005824", "f7fcfde5f5f9ccece699d8c966c2a441ae76238b45006d2c00441b").map(colors);
  var BuGn = ramp(scheme$9);

  var scheme$a = new Array(3).concat("e0ecf49ebcda8856a7", "edf8fbb3cde38c96c688419d", "edf8fbb3cde38c96c68856a7810f7c", "edf8fbbfd3e69ebcda8c96c68856a7810f7c", "edf8fbbfd3e69ebcda8c96c68c6bb188419d6e016b", "f7fcfde0ecf4bfd3e69ebcda8c96c68c6bb188419d6e016b", "f7fcfde0ecf4bfd3e69ebcda8c96c68c6bb188419d810f7c4d004b").map(colors);
  var BuPu = ramp(scheme$a);

  var scheme$b = new Array(3).concat("e0f3dba8ddb543a2ca", "f0f9e8bae4bc7bccc42b8cbe", "f0f9e8bae4bc7bccc443a2ca0868ac", "f0f9e8ccebc5a8ddb57bccc443a2ca0868ac", "f0f9e8ccebc5a8ddb57bccc44eb3d32b8cbe08589e", "f7fcf0e0f3dbccebc5a8ddb57bccc44eb3d32b8cbe08589e", "f7fcf0e0f3dbccebc5a8ddb57bccc44eb3d32b8cbe0868ac084081").map(colors);
  var GnBu = ramp(scheme$b);

  var scheme$c = new Array(3).concat("fee8c8fdbb84e34a33", "fef0d9fdcc8afc8d59d7301f", "fef0d9fdcc8afc8d59e34a33b30000", "fef0d9fdd49efdbb84fc8d59e34a33b30000", "fef0d9fdd49efdbb84fc8d59ef6548d7301f990000", "fff7ecfee8c8fdd49efdbb84fc8d59ef6548d7301f990000", "fff7ecfee8c8fdd49efdbb84fc8d59ef6548d7301fb300007f0000").map(colors);
  var OrRd = ramp(scheme$c);

  var scheme$d = new Array(3).concat("ece2f0a6bddb1c9099", "f6eff7bdc9e167a9cf02818a", "f6eff7bdc9e167a9cf1c9099016c59", "f6eff7d0d1e6a6bddb67a9cf1c9099016c59", "f6eff7d0d1e6a6bddb67a9cf3690c002818a016450", "fff7fbece2f0d0d1e6a6bddb67a9cf3690c002818a016450", "fff7fbece2f0d0d1e6a6bddb67a9cf3690c002818a016c59014636").map(colors);
  var PuBuGn = ramp(scheme$d);

  var scheme$e = new Array(3).concat("ece7f2a6bddb2b8cbe", "f1eef6bdc9e174a9cf0570b0", "f1eef6bdc9e174a9cf2b8cbe045a8d", "f1eef6d0d1e6a6bddb74a9cf2b8cbe045a8d", "f1eef6d0d1e6a6bddb74a9cf3690c00570b0034e7b", "fff7fbece7f2d0d1e6a6bddb74a9cf3690c00570b0034e7b", "fff7fbece7f2d0d1e6a6bddb74a9cf3690c00570b0045a8d023858").map(colors);
  var PuBu = ramp(scheme$e);

  var scheme$f = new Array(3).concat("e7e1efc994c7dd1c77", "f1eef6d7b5d8df65b0ce1256", "f1eef6d7b5d8df65b0dd1c77980043", "f1eef6d4b9dac994c7df65b0dd1c77980043", "f1eef6d4b9dac994c7df65b0e7298ace125691003f", "f7f4f9e7e1efd4b9dac994c7df65b0e7298ace125691003f", "f7f4f9e7e1efd4b9dac994c7df65b0e7298ace125698004367001f").map(colors);
  var PuRd = ramp(scheme$f);

  var scheme$g = new Array(3).concat("fde0ddfa9fb5c51b8a", "feebe2fbb4b9f768a1ae017e", "feebe2fbb4b9f768a1c51b8a7a0177", "feebe2fcc5c0fa9fb5f768a1c51b8a7a0177", "feebe2fcc5c0fa9fb5f768a1dd3497ae017e7a0177", "fff7f3fde0ddfcc5c0fa9fb5f768a1dd3497ae017e7a0177", "fff7f3fde0ddfcc5c0fa9fb5f768a1dd3497ae017e7a017749006a").map(colors);
  var RdPu = ramp(scheme$g);

  var scheme$h = new Array(3).concat("edf8b17fcdbb2c7fb8", "ffffcca1dab441b6c4225ea8", "ffffcca1dab441b6c42c7fb8253494", "ffffccc7e9b47fcdbb41b6c42c7fb8253494", "ffffccc7e9b47fcdbb41b6c41d91c0225ea80c2c84", "ffffd9edf8b1c7e9b47fcdbb41b6c41d91c0225ea80c2c84", "ffffd9edf8b1c7e9b47fcdbb41b6c41d91c0225ea8253494081d58").map(colors);
  var YlGnBu = ramp(scheme$h);

  var scheme$i = new Array(3).concat("f7fcb9addd8e31a354", "ffffccc2e69978c679238443", "ffffccc2e69978c67931a354006837", "ffffccd9f0a3addd8e78c67931a354006837", "ffffccd9f0a3addd8e78c67941ab5d238443005a32", "ffffe5f7fcb9d9f0a3addd8e78c67941ab5d238443005a32", "ffffe5f7fcb9d9f0a3addd8e78c67941ab5d238443006837004529").map(colors);
  var YlGn = ramp(scheme$i);

  var scheme$j = new Array(3).concat("fff7bcfec44fd95f0e", "ffffd4fed98efe9929cc4c02", "ffffd4fed98efe9929d95f0e993404", "ffffd4fee391fec44ffe9929d95f0e993404", "ffffd4fee391fec44ffe9929ec7014cc4c028c2d04", "ffffe5fff7bcfee391fec44ffe9929ec7014cc4c028c2d04", "ffffe5fff7bcfee391fec44ffe9929ec7014cc4c02993404662506").map(colors);
  var YlOrBr = ramp(scheme$j);

  var scheme$k = new Array(3).concat("ffeda0feb24cf03b20", "ffffb2fecc5cfd8d3ce31a1c", "ffffb2fecc5cfd8d3cf03b20bd0026", "ffffb2fed976feb24cfd8d3cf03b20bd0026", "ffffb2fed976feb24cfd8d3cfc4e2ae31a1cb10026", "ffffccffeda0fed976feb24cfd8d3cfc4e2ae31a1cb10026", "ffffccffeda0fed976feb24cfd8d3cfc4e2ae31a1cbd0026800026").map(colors);
  var YlOrRd = ramp(scheme$k);

  var scheme$l = new Array(3).concat("deebf79ecae13182bd", "eff3ffbdd7e76baed62171b5", "eff3ffbdd7e76baed63182bd08519c", "eff3ffc6dbef9ecae16baed63182bd08519c", "eff3ffc6dbef9ecae16baed64292c62171b5084594", "f7fbffdeebf7c6dbef9ecae16baed64292c62171b5084594", "f7fbffdeebf7c6dbef9ecae16baed64292c62171b508519c08306b").map(colors);
  var Blues = ramp(scheme$l);

  var scheme$m = new Array(3).concat("e5f5e0a1d99b31a354", "edf8e9bae4b374c476238b45", "edf8e9bae4b374c47631a354006d2c", "edf8e9c7e9c0a1d99b74c47631a354006d2c", "edf8e9c7e9c0a1d99b74c47641ab5d238b45005a32", "f7fcf5e5f5e0c7e9c0a1d99b74c47641ab5d238b45005a32", "f7fcf5e5f5e0c7e9c0a1d99b74c47641ab5d238b45006d2c00441b").map(colors);
  var Greens = ramp(scheme$m);

  var scheme$n = new Array(3).concat("f0f0f0bdbdbd636363", "f7f7f7cccccc969696525252", "f7f7f7cccccc969696636363252525", "f7f7f7d9d9d9bdbdbd969696636363252525", "f7f7f7d9d9d9bdbdbd969696737373525252252525", "fffffff0f0f0d9d9d9bdbdbd969696737373525252252525", "fffffff0f0f0d9d9d9bdbdbd969696737373525252252525000000").map(colors);
  var Greys = ramp(scheme$n);

  var scheme$o = new Array(3).concat("efedf5bcbddc756bb1", "f2f0f7cbc9e29e9ac86a51a3", "f2f0f7cbc9e29e9ac8756bb154278f", "f2f0f7dadaebbcbddc9e9ac8756bb154278f", "f2f0f7dadaebbcbddc9e9ac8807dba6a51a34a1486", "fcfbfdefedf5dadaebbcbddc9e9ac8807dba6a51a34a1486", "fcfbfdefedf5dadaebbcbddc9e9ac8807dba6a51a354278f3f007d").map(colors);
  var Purples = ramp(scheme$o);

  var scheme$p = new Array(3).concat("fee0d2fc9272de2d26", "fee5d9fcae91fb6a4acb181d", "fee5d9fcae91fb6a4ade2d26a50f15", "fee5d9fcbba1fc9272fb6a4ade2d26a50f15", "fee5d9fcbba1fc9272fb6a4aef3b2ccb181d99000d", "fff5f0fee0d2fcbba1fc9272fb6a4aef3b2ccb181d99000d", "fff5f0fee0d2fcbba1fc9272fb6a4aef3b2ccb181da50f1567000d").map(colors);
  var Reds = ramp(scheme$p);

  var scheme$q = new Array(3).concat("fee6cefdae6be6550d", "feeddefdbe85fd8d3cd94701", "feeddefdbe85fd8d3ce6550da63603", "feeddefdd0a2fdae6bfd8d3ce6550da63603", "feeddefdd0a2fdae6bfd8d3cf16913d948018c2d04", "fff5ebfee6cefdd0a2fdae6bfd8d3cf16913d948018c2d04", "fff5ebfee6cefdd0a2fdae6bfd8d3cf16913d94801a636037f2704").map(colors);
  var Oranges = ramp(scheme$q);

  var cubehelix$3 = cubehelixLong(cubehelix(300, 0.5, 0.0), cubehelix(-240, 0.5, 1.0));

  var warm = cubehelixLong(cubehelix(-100, 0.75, 0.35), cubehelix(80, 1.50, 0.8));
  var cool = cubehelixLong(cubehelix(260, 0.75, 0.35), cubehelix(80, 1.50, 0.8));
  var c = cubehelix();
  function rainbow (t) {
    if (t < 0 || t > 1) t -= Math.floor(t);
    var ts = Math.abs(t - 0.5);
    c.h = 360 * t - 100;
    c.s = 1.5 - 1.5 * ts;
    c.l = 0.8 - 0.9 * ts;
    return c + "";
  }

  var c$1 = rgb(),
      pi_1_3 = Math.PI / 3,
      pi_2_3 = Math.PI * 2 / 3;
  function sinebow (t) {
    var x;
    t = (0.5 - t) * Math.PI;
    c$1.r = 255 * (x = Math.sin(t)) * x;
    c$1.g = 255 * (x = Math.sin(t + pi_1_3)) * x;
    c$1.b = 255 * (x = Math.sin(t + pi_2_3)) * x;
    return c$1 + "";
  }

  function ramp$1(range) {
    var n = range.length;
    return function (t) {
      return range[Math.max(0, Math.min(n - 1, Math.floor(t * n)))];
    };
  }

  var viridis = ramp$1(colors("44015444025645045745055946075a46085c460a5d460b5e470d60470e6147106347116447136548146748166848176948186a481a6c481b6d481c6e481d6f481f70482071482173482374482475482576482677482878482979472a7a472c7a472d7b472e7c472f7d46307e46327e46337f463480453581453781453882443983443a83443b84433d84433e85423f854240864241864142874144874045884046883f47883f48893e49893e4a893e4c8a3d4d8a3d4e8a3c4f8a3c508b3b518b3b528b3a538b3a548c39558c39568c38588c38598c375a8c375b8d365c8d365d8d355e8d355f8d34608d34618d33628d33638d32648e32658e31668e31678e31688e30698e306a8e2f6b8e2f6c8e2e6d8e2e6e8e2e6f8e2d708e2d718e2c718e2c728e2c738e2b748e2b758e2a768e2a778e2a788e29798e297a8e297b8e287c8e287d8e277e8e277f8e27808e26818e26828e26828e25838e25848e25858e24868e24878e23888e23898e238a8d228b8d228c8d228d8d218e8d218f8d21908d21918c20928c20928c20938c1f948c1f958b1f968b1f978b1f988b1f998a1f9a8a1e9b8a1e9c891e9d891f9e891f9f881fa0881fa1881fa1871fa28720a38620a48621a58521a68522a78522a88423a98324aa8325ab8225ac8226ad8127ad8128ae8029af7f2ab07f2cb17e2db27d2eb37c2fb47c31b57b32b67a34b67935b77937b87838b9773aba763bbb753dbc743fbc7340bd7242be7144bf7046c06f48c16e4ac16d4cc26c4ec36b50c46a52c56954c56856c66758c7655ac8645cc8635ec96260ca6063cb5f65cb5e67cc5c69cd5b6ccd5a6ece5870cf5773d05675d05477d1537ad1517cd2507fd34e81d34d84d44b86d54989d5488bd6468ed64590d74393d74195d84098d83e9bd93c9dd93ba0da39a2da37a5db36a8db34aadc32addc30b0dd2fb2dd2db5de2bb8de29bade28bddf26c0df25c2df23c5e021c8e020cae11fcde11dd0e11cd2e21bd5e21ad8e219dae319dde318dfe318e2e418e5e419e7e419eae51aece51befe51cf1e51df4e61ef6e620f8e621fbe723fde725"));
  var magma = ramp$1(colors("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"));
  var inferno = ramp$1(colors("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"));
  var plasma = ramp$1(colors("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"));

  function constant$b (x) {
    return function constant() {
      return x;
    };
  }

  var abs$1 = Math.abs;
  var atan2$1 = Math.atan2;
  var cos$2 = Math.cos;
  var max$2 = Math.max;
  var min$1 = Math.min;
  var sin$2 = Math.sin;
  var sqrt$2 = Math.sqrt;
  var epsilon$3 = 1e-12;
  var pi$4 = Math.PI;
  var halfPi$3 = pi$4 / 2;
  var tau$4 = 2 * pi$4;
  function acos$1(x) {
    return x > 1 ? 0 : x < -1 ? pi$4 : Math.acos(x);
  }
  function asin$1(x) {
    return x >= 1 ? halfPi$3 : x <= -1 ? -halfPi$3 : Math.asin(x);
  }

  function arcInnerRadius(d) {
    return d.innerRadius;
  }

  function arcOuterRadius(d) {
    return d.outerRadius;
  }

  function arcStartAngle(d) {
    return d.startAngle;
  }

  function arcEndAngle(d) {
    return d.endAngle;
  }

  function arcPadAngle(d) {
    return d && d.padAngle; // Note: optional!
  }

  function intersect(x0, y0, x1, y1, x2, y2, x3, y3) {
    var x10 = x1 - x0,
        y10 = y1 - y0,
        x32 = x3 - x2,
        y32 = y3 - y2,
        t = y32 * x10 - x32 * y10;
    if (t * t < epsilon$3) return;
    t = (x32 * (y0 - y2) - y32 * (x0 - x2)) / t;
    return [x0 + t * x10, y0 + t * y10];
  } // Compute perpendicular offset line of length rc.
  // http://mathworld.wolfram.com/Circle-LineIntersection.html


  function cornerTangents(x0, y0, x1, y1, r1, rc, cw) {
    var x01 = x0 - x1,
        y01 = y0 - y1,
        lo = (cw ? rc : -rc) / sqrt$2(x01 * x01 + y01 * y01),
        ox = lo * y01,
        oy = -lo * x01,
        x11 = x0 + ox,
        y11 = y0 + oy,
        x10 = x1 + ox,
        y10 = y1 + oy,
        x00 = (x11 + x10) / 2,
        y00 = (y11 + y10) / 2,
        dx = x10 - x11,
        dy = y10 - y11,
        d2 = dx * dx + dy * dy,
        r = r1 - rc,
        D = x11 * y10 - x10 * y11,
        d = (dy < 0 ? -1 : 1) * sqrt$2(max$2(0, r * r * d2 - D * D)),
        cx0 = (D * dy - dx * d) / d2,
        cy0 = (-D * dx - dy * d) / d2,
        cx1 = (D * dy + dx * d) / d2,
        cy1 = (-D * dx + dy * d) / d2,
        dx0 = cx0 - x00,
        dy0 = cy0 - y00,
        dx1 = cx1 - x00,
        dy1 = cy1 - y00; // Pick the closer of the two intersection points.
    // TODO Is there a faster way to determine which intersection to use?

    if (dx0 * dx0 + dy0 * dy0 > dx1 * dx1 + dy1 * dy1) cx0 = cx1, cy0 = cy1;
    return {
      cx: cx0,
      cy: cy0,
      x01: -ox,
      y01: -oy,
      x11: cx0 * (r1 / r - 1),
      y11: cy0 * (r1 / r - 1)
    };
  }

  function arc () {
    var innerRadius = arcInnerRadius,
        outerRadius = arcOuterRadius,
        cornerRadius = constant$b(0),
        padRadius = null,
        startAngle = arcStartAngle,
        endAngle = arcEndAngle,
        padAngle = arcPadAngle,
        context = null;

    function arc() {
      var buffer,
          r,
          r0 = +innerRadius.apply(this, arguments),
          r1 = +outerRadius.apply(this, arguments),
          a0 = startAngle.apply(this, arguments) - halfPi$3,
          a1 = endAngle.apply(this, arguments) - halfPi$3,
          da = abs$1(a1 - a0),
          cw = a1 > a0;
      if (!context) context = buffer = path(); // Ensure that the outer radius is always larger than the inner radius.

      if (r1 < r0) r = r1, r1 = r0, r0 = r; // Is it a point?

      if (!(r1 > epsilon$3)) context.moveTo(0, 0); // Or is it a circle or annulus?
      else if (da > tau$4 - epsilon$3) {
          context.moveTo(r1 * cos$2(a0), r1 * sin$2(a0));
          context.arc(0, 0, r1, a0, a1, !cw);

          if (r0 > epsilon$3) {
            context.moveTo(r0 * cos$2(a1), r0 * sin$2(a1));
            context.arc(0, 0, r0, a1, a0, cw);
          }
        } // Or is it a circular or annular sector?
        else {
            var a01 = a0,
                a11 = a1,
                a00 = a0,
                a10 = a1,
                da0 = da,
                da1 = da,
                ap = padAngle.apply(this, arguments) / 2,
                rp = ap > epsilon$3 && (padRadius ? +padRadius.apply(this, arguments) : sqrt$2(r0 * r0 + r1 * r1)),
                rc = min$1(abs$1(r1 - r0) / 2, +cornerRadius.apply(this, arguments)),
                rc0 = rc,
                rc1 = rc,
                t0,
                t1; // Apply padding? Note that since r1 ≥ r0, da1 ≥ da0.

            if (rp > epsilon$3) {
              var p0 = asin$1(rp / r0 * sin$2(ap)),
                  p1 = asin$1(rp / r1 * sin$2(ap));
              if ((da0 -= p0 * 2) > epsilon$3) p0 *= cw ? 1 : -1, a00 += p0, a10 -= p0;else da0 = 0, a00 = a10 = (a0 + a1) / 2;
              if ((da1 -= p1 * 2) > epsilon$3) p1 *= cw ? 1 : -1, a01 += p1, a11 -= p1;else da1 = 0, a01 = a11 = (a0 + a1) / 2;
            }

            var x01 = r1 * cos$2(a01),
                y01 = r1 * sin$2(a01),
                x10 = r0 * cos$2(a10),
                y10 = r0 * sin$2(a10); // Apply rounded corners?

            if (rc > epsilon$3) {
              var x11 = r1 * cos$2(a11),
                  y11 = r1 * sin$2(a11),
                  x00 = r0 * cos$2(a00),
                  y00 = r0 * sin$2(a00),
                  oc; // Restrict the corner radius according to the sector angle.

              if (da < pi$4 && (oc = intersect(x01, y01, x00, y00, x11, y11, x10, y10))) {
                var ax = x01 - oc[0],
                    ay = y01 - oc[1],
                    bx = x11 - oc[0],
                    by = y11 - oc[1],
                    kc = 1 / sin$2(acos$1((ax * bx + ay * by) / (sqrt$2(ax * ax + ay * ay) * sqrt$2(bx * bx + by * by))) / 2),
                    lc = sqrt$2(oc[0] * oc[0] + oc[1] * oc[1]);
                rc0 = min$1(rc, (r0 - lc) / (kc - 1));
                rc1 = min$1(rc, (r1 - lc) / (kc + 1));
              }
            } // Is the sector collapsed to a line?


            if (!(da1 > epsilon$3)) context.moveTo(x01, y01); // Does the sector’s outer ring have rounded corners?
            else if (rc1 > epsilon$3) {
                t0 = cornerTangents(x00, y00, x01, y01, r1, rc1, cw);
                t1 = cornerTangents(x11, y11, x10, y10, r1, rc1, cw);
                context.moveTo(t0.cx + t0.x01, t0.cy + t0.y01); // Have the corners merged?

                if (rc1 < rc) context.arc(t0.cx, t0.cy, rc1, atan2$1(t0.y01, t0.x01), atan2$1(t1.y01, t1.x01), !cw); // Otherwise, draw the two corners and the ring.
                else {
                    context.arc(t0.cx, t0.cy, rc1, atan2$1(t0.y01, t0.x01), atan2$1(t0.y11, t0.x11), !cw);
                    context.arc(0, 0, r1, atan2$1(t0.cy + t0.y11, t0.cx + t0.x11), atan2$1(t1.cy + t1.y11, t1.cx + t1.x11), !cw);
                    context.arc(t1.cx, t1.cy, rc1, atan2$1(t1.y11, t1.x11), atan2$1(t1.y01, t1.x01), !cw);
                  }
              } // Or is the outer ring just a circular arc?
              else context.moveTo(x01, y01), context.arc(0, 0, r1, a01, a11, !cw); // Is there no inner ring, and it’s a circular sector?
            // Or perhaps it’s an annular sector collapsed due to padding?

            if (!(r0 > epsilon$3) || !(da0 > epsilon$3)) context.lineTo(x10, y10); // Does the sector’s inner ring (or point) have rounded corners?
            else if (rc0 > epsilon$3) {
                t0 = cornerTangents(x10, y10, x11, y11, r0, -rc0, cw);
                t1 = cornerTangents(x01, y01, x00, y00, r0, -rc0, cw);
                context.lineTo(t0.cx + t0.x01, t0.cy + t0.y01); // Have the corners merged?

                if (rc0 < rc) context.arc(t0.cx, t0.cy, rc0, atan2$1(t0.y01, t0.x01), atan2$1(t1.y01, t1.x01), !cw); // Otherwise, draw the two corners and the ring.
                else {
                    context.arc(t0.cx, t0.cy, rc0, atan2$1(t0.y01, t0.x01), atan2$1(t0.y11, t0.x11), !cw);
                    context.arc(0, 0, r0, atan2$1(t0.cy + t0.y11, t0.cx + t0.x11), atan2$1(t1.cy + t1.y11, t1.cx + t1.x11), cw);
                    context.arc(t1.cx, t1.cy, rc0, atan2$1(t1.y11, t1.x11), atan2$1(t1.y01, t1.x01), !cw);
                  }
              } // Or is the inner ring just a circular arc?
              else context.arc(0, 0, r0, a10, a00, cw);
          }
      context.closePath();
      if (buffer) return context = null, buffer + "" || null;
    }

    arc.centroid = function () {
      var r = (+innerRadius.apply(this, arguments) + +outerRadius.apply(this, arguments)) / 2,
          a = (+startAngle.apply(this, arguments) + +endAngle.apply(this, arguments)) / 2 - pi$4 / 2;
      return [cos$2(a) * r, sin$2(a) * r];
    };

    arc.innerRadius = function (_) {
      return arguments.length ? (innerRadius = typeof _ === "function" ? _ : constant$b(+_), arc) : innerRadius;
    };

    arc.outerRadius = function (_) {
      return arguments.length ? (outerRadius = typeof _ === "function" ? _ : constant$b(+_), arc) : outerRadius;
    };

    arc.cornerRadius = function (_) {
      return arguments.length ? (cornerRadius = typeof _ === "function" ? _ : constant$b(+_), arc) : cornerRadius;
    };

    arc.padRadius = function (_) {
      return arguments.length ? (padRadius = _ == null ? null : typeof _ === "function" ? _ : constant$b(+_), arc) : padRadius;
    };

    arc.startAngle = function (_) {
      return arguments.length ? (startAngle = typeof _ === "function" ? _ : constant$b(+_), arc) : startAngle;
    };

    arc.endAngle = function (_) {
      return arguments.length ? (endAngle = typeof _ === "function" ? _ : constant$b(+_), arc) : endAngle;
    };

    arc.padAngle = function (_) {
      return arguments.length ? (padAngle = typeof _ === "function" ? _ : constant$b(+_), arc) : padAngle;
    };

    arc.context = function (_) {
      return arguments.length ? (context = _ == null ? null : _, arc) : context;
    };

    return arc;
  }

  function Linear(context) {
    this._context = context;
  }

  Linear.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._line || this._line !== 0 && this._point === 1) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
          break;

        case 1:
          this._point = 2;
        // proceed

        default:
          this._context.lineTo(x, y);

          break;
      }
    }
  };
  function curveLinear (context) {
    return new Linear(context);
  }

  function x$3(p) {
    return p[0];
  }
  function y$3(p) {
    return p[1];
  }

  function line () {
    var x$$1 = x$3,
        y$$1 = y$3,
        defined = constant$b(true),
        context = null,
        curve = curveLinear,
        output = null;

    function line(data) {
      var i,
          n = data.length,
          d,
          defined0 = false,
          buffer;
      if (context == null) output = curve(buffer = path());

      for (i = 0; i <= n; ++i) {
        if (!(i < n && defined(d = data[i], i, data)) === defined0) {
          if (defined0 = !defined0) output.lineStart();else output.lineEnd();
        }

        if (defined0) output.point(+x$$1(d, i, data), +y$$1(d, i, data));
      }

      if (buffer) return output = null, buffer + "" || null;
    }

    line.x = function (_) {
      return arguments.length ? (x$$1 = typeof _ === "function" ? _ : constant$b(+_), line) : x$$1;
    };

    line.y = function (_) {
      return arguments.length ? (y$$1 = typeof _ === "function" ? _ : constant$b(+_), line) : y$$1;
    };

    line.defined = function (_) {
      return arguments.length ? (defined = typeof _ === "function" ? _ : constant$b(!!_), line) : defined;
    };

    line.curve = function (_) {
      return arguments.length ? (curve = _, context != null && (output = curve(context)), line) : curve;
    };

    line.context = function (_) {
      return arguments.length ? (_ == null ? context = output = null : output = curve(context = _), line) : context;
    };

    return line;
  }

  function area$3 () {
    var x0 = x$3,
        x1 = null,
        y0 = constant$b(0),
        y1 = y$3,
        defined = constant$b(true),
        context = null,
        curve = curveLinear,
        output = null;

    function area(data) {
      var i,
          j,
          k,
          n = data.length,
          d,
          defined0 = false,
          buffer,
          x0z = new Array(n),
          y0z = new Array(n);
      if (context == null) output = curve(buffer = path());

      for (i = 0; i <= n; ++i) {
        if (!(i < n && defined(d = data[i], i, data)) === defined0) {
          if (defined0 = !defined0) {
            j = i;
            output.areaStart();
            output.lineStart();
          } else {
            output.lineEnd();
            output.lineStart();

            for (k = i - 1; k >= j; --k) {
              output.point(x0z[k], y0z[k]);
            }

            output.lineEnd();
            output.areaEnd();
          }
        }

        if (defined0) {
          x0z[i] = +x0(d, i, data), y0z[i] = +y0(d, i, data);
          output.point(x1 ? +x1(d, i, data) : x0z[i], y1 ? +y1(d, i, data) : y0z[i]);
        }
      }

      if (buffer) return output = null, buffer + "" || null;
    }

    function arealine() {
      return line().defined(defined).curve(curve).context(context);
    }

    area.x = function (_) {
      return arguments.length ? (x0 = typeof _ === "function" ? _ : constant$b(+_), x1 = null, area) : x0;
    };

    area.x0 = function (_) {
      return arguments.length ? (x0 = typeof _ === "function" ? _ : constant$b(+_), area) : x0;
    };

    area.x1 = function (_) {
      return arguments.length ? (x1 = _ == null ? null : typeof _ === "function" ? _ : constant$b(+_), area) : x1;
    };

    area.y = function (_) {
      return arguments.length ? (y0 = typeof _ === "function" ? _ : constant$b(+_), y1 = null, area) : y0;
    };

    area.y0 = function (_) {
      return arguments.length ? (y0 = typeof _ === "function" ? _ : constant$b(+_), area) : y0;
    };

    area.y1 = function (_) {
      return arguments.length ? (y1 = _ == null ? null : typeof _ === "function" ? _ : constant$b(+_), area) : y1;
    };

    area.lineX0 = area.lineY0 = function () {
      return arealine().x(x0).y(y0);
    };

    area.lineY1 = function () {
      return arealine().x(x0).y(y1);
    };

    area.lineX1 = function () {
      return arealine().x(x1).y(y0);
    };

    area.defined = function (_) {
      return arguments.length ? (defined = typeof _ === "function" ? _ : constant$b(!!_), area) : defined;
    };

    area.curve = function (_) {
      return arguments.length ? (curve = _, context != null && (output = curve(context)), area) : curve;
    };

    area.context = function (_) {
      return arguments.length ? (_ == null ? context = output = null : output = curve(context = _), area) : context;
    };

    return area;
  }

  function descending$1 (a, b) {
    return b < a ? -1 : b > a ? 1 : b >= a ? 0 : NaN;
  }

  function identity$8 (d) {
    return d;
  }

  function pie () {
    var value = identity$8,
        sortValues = descending$1,
        sort = null,
        startAngle = constant$b(0),
        endAngle = constant$b(tau$4),
        padAngle = constant$b(0);

    function pie(data) {
      var i,
          n = data.length,
          j,
          k,
          sum = 0,
          index = new Array(n),
          arcs = new Array(n),
          a0 = +startAngle.apply(this, arguments),
          da = Math.min(tau$4, Math.max(-tau$4, endAngle.apply(this, arguments) - a0)),
          a1,
          p = Math.min(Math.abs(da) / n, padAngle.apply(this, arguments)),
          pa = p * (da < 0 ? -1 : 1),
          v;

      for (i = 0; i < n; ++i) {
        if ((v = arcs[index[i] = i] = +value(data[i], i, data)) > 0) {
          sum += v;
        }
      } // Optionally sort the arcs by previously-computed values or by data.


      if (sortValues != null) index.sort(function (i, j) {
        return sortValues(arcs[i], arcs[j]);
      });else if (sort != null) index.sort(function (i, j) {
        return sort(data[i], data[j]);
      }); // Compute the arcs! They are stored in the original data's order.

      for (i = 0, k = sum ? (da - n * pa) / sum : 0; i < n; ++i, a0 = a1) {
        j = index[i], v = arcs[j], a1 = a0 + (v > 0 ? v * k : 0) + pa, arcs[j] = {
          data: data[j],
          index: i,
          value: v,
          startAngle: a0,
          endAngle: a1,
          padAngle: p
        };
      }

      return arcs;
    }

    pie.value = function (_) {
      return arguments.length ? (value = typeof _ === "function" ? _ : constant$b(+_), pie) : value;
    };

    pie.sortValues = function (_) {
      return arguments.length ? (sortValues = _, sort = null, pie) : sortValues;
    };

    pie.sort = function (_) {
      return arguments.length ? (sort = _, sortValues = null, pie) : sort;
    };

    pie.startAngle = function (_) {
      return arguments.length ? (startAngle = typeof _ === "function" ? _ : constant$b(+_), pie) : startAngle;
    };

    pie.endAngle = function (_) {
      return arguments.length ? (endAngle = typeof _ === "function" ? _ : constant$b(+_), pie) : endAngle;
    };

    pie.padAngle = function (_) {
      return arguments.length ? (padAngle = typeof _ === "function" ? _ : constant$b(+_), pie) : padAngle;
    };

    return pie;
  }

  var curveRadialLinear = curveRadial(curveLinear);

  function Radial(curve) {
    this._curve = curve;
  }

  Radial.prototype = {
    areaStart: function areaStart() {
      this._curve.areaStart();
    },
    areaEnd: function areaEnd() {
      this._curve.areaEnd();
    },
    lineStart: function lineStart() {
      this._curve.lineStart();
    },
    lineEnd: function lineEnd() {
      this._curve.lineEnd();
    },
    point: function point(a, r) {
      this._curve.point(r * Math.sin(a), r * -Math.cos(a));
    }
  };
  function curveRadial(curve) {
    function radial(context) {
      return new Radial(curve(context));
    }

    radial._curve = curve;
    return radial;
  }

  function lineRadial(l) {
    var c = l.curve;
    l.angle = l.x, delete l.x;
    l.radius = l.y, delete l.y;

    l.curve = function (_) {
      return arguments.length ? c(curveRadial(_)) : c()._curve;
    };

    return l;
  }
  function lineRadial$1 () {
    return lineRadial(line().curve(curveRadialLinear));
  }

  function areaRadial () {
    var a = area$3().curve(curveRadialLinear),
        c = a.curve,
        x0 = a.lineX0,
        x1 = a.lineX1,
        y0 = a.lineY0,
        y1 = a.lineY1;
    a.angle = a.x, delete a.x;
    a.startAngle = a.x0, delete a.x0;
    a.endAngle = a.x1, delete a.x1;
    a.radius = a.y, delete a.y;
    a.innerRadius = a.y0, delete a.y0;
    a.outerRadius = a.y1, delete a.y1;
    a.lineStartAngle = function () {
      return lineRadial(x0());
    }, delete a.lineX0;
    a.lineEndAngle = function () {
      return lineRadial(x1());
    }, delete a.lineX1;
    a.lineInnerRadius = function () {
      return lineRadial(y0());
    }, delete a.lineY0;
    a.lineOuterRadius = function () {
      return lineRadial(y1());
    }, delete a.lineY1;

    a.curve = function (_) {
      return arguments.length ? c(curveRadial(_)) : c()._curve;
    };

    return a;
  }

  function pointRadial (x, y) {
    return [(y = +y) * Math.cos(x -= Math.PI / 2), y * Math.sin(x)];
  }

  var slice$6 = Array.prototype.slice;

  function linkSource(d) {
    return d.source;
  }

  function linkTarget(d) {
    return d.target;
  }

  function link$2(curve) {
    var source = linkSource,
        target = linkTarget,
        x$$1 = x$3,
        y$$1 = y$3,
        context = null;

    function link() {
      var buffer,
          argv = slice$6.call(arguments),
          s = source.apply(this, argv),
          t = target.apply(this, argv);
      if (!context) context = buffer = path();
      curve(context, +x$$1.apply(this, (argv[0] = s, argv)), +y$$1.apply(this, argv), +x$$1.apply(this, (argv[0] = t, argv)), +y$$1.apply(this, argv));
      if (buffer) return context = null, buffer + "" || null;
    }

    link.source = function (_) {
      return arguments.length ? (source = _, link) : source;
    };

    link.target = function (_) {
      return arguments.length ? (target = _, link) : target;
    };

    link.x = function (_) {
      return arguments.length ? (x$$1 = typeof _ === "function" ? _ : constant$b(+_), link) : x$$1;
    };

    link.y = function (_) {
      return arguments.length ? (y$$1 = typeof _ === "function" ? _ : constant$b(+_), link) : y$$1;
    };

    link.context = function (_) {
      return arguments.length ? (context = _ == null ? null : _, link) : context;
    };

    return link;
  }

  function curveHorizontal(context, x0, y0, x1, y1) {
    context.moveTo(x0, y0);
    context.bezierCurveTo(x0 = (x0 + x1) / 2, y0, x0, y1, x1, y1);
  }

  function curveVertical(context, x0, y0, x1, y1) {
    context.moveTo(x0, y0);
    context.bezierCurveTo(x0, y0 = (y0 + y1) / 2, x1, y0, x1, y1);
  }

  function curveRadial$1(context, x0, y0, x1, y1) {
    var p0 = pointRadial(x0, y0),
        p1 = pointRadial(x0, y0 = (y0 + y1) / 2),
        p2 = pointRadial(x1, y0),
        p3 = pointRadial(x1, y1);
    context.moveTo(p0[0], p0[1]);
    context.bezierCurveTo(p1[0], p1[1], p2[0], p2[1], p3[0], p3[1]);
  }

  function linkHorizontal() {
    return link$2(curveHorizontal);
  }
  function linkVertical() {
    return link$2(curveVertical);
  }
  function linkRadial() {
    var l = link$2(curveRadial$1);
    l.angle = l.x, delete l.x;
    l.radius = l.y, delete l.y;
    return l;
  }

  var circle$2 = {
    draw: function draw(context, size) {
      var r = Math.sqrt(size / pi$4);
      context.moveTo(r, 0);
      context.arc(0, 0, r, 0, tau$4);
    }
  };

  var cross$2 = {
    draw: function draw(context, size) {
      var r = Math.sqrt(size / 5) / 2;
      context.moveTo(-3 * r, -r);
      context.lineTo(-r, -r);
      context.lineTo(-r, -3 * r);
      context.lineTo(r, -3 * r);
      context.lineTo(r, -r);
      context.lineTo(3 * r, -r);
      context.lineTo(3 * r, r);
      context.lineTo(r, r);
      context.lineTo(r, 3 * r);
      context.lineTo(-r, 3 * r);
      context.lineTo(-r, r);
      context.lineTo(-3 * r, r);
      context.closePath();
    }
  };

  var tan30 = Math.sqrt(1 / 3),
      tan30_2 = tan30 * 2;
  var diamond = {
    draw: function draw(context, size) {
      var y = Math.sqrt(size / tan30_2),
          x = y * tan30;
      context.moveTo(0, -y);
      context.lineTo(x, 0);
      context.lineTo(0, y);
      context.lineTo(-x, 0);
      context.closePath();
    }
  };

  var ka = 0.89081309152928522810,
      kr = Math.sin(pi$4 / 10) / Math.sin(7 * pi$4 / 10),
      kx = Math.sin(tau$4 / 10) * kr,
      ky = -Math.cos(tau$4 / 10) * kr;
  var star = {
    draw: function draw(context, size) {
      var r = Math.sqrt(size * ka),
          x = kx * r,
          y = ky * r;
      context.moveTo(0, -r);
      context.lineTo(x, y);

      for (var i = 1; i < 5; ++i) {
        var a = tau$4 * i / 5,
            c = Math.cos(a),
            s = Math.sin(a);
        context.lineTo(s * r, -c * r);
        context.lineTo(c * x - s * y, s * x + c * y);
      }

      context.closePath();
    }
  };

  var square = {
    draw: function draw(context, size) {
      var w = Math.sqrt(size),
          x = -w / 2;
      context.rect(x, x, w, w);
    }
  };

  var sqrt3 = Math.sqrt(3);
  var triangle = {
    draw: function draw(context, size) {
      var y = -Math.sqrt(size / (sqrt3 * 3));
      context.moveTo(0, y * 2);
      context.lineTo(-sqrt3 * y, -y);
      context.lineTo(sqrt3 * y, -y);
      context.closePath();
    }
  };

  var c$2 = -0.5,
      s = Math.sqrt(3) / 2,
      k = 1 / Math.sqrt(12),
      a = (k / 2 + 1) * 3;
  var wye = {
    draw: function draw(context, size) {
      var r = Math.sqrt(size / a),
          x0 = r / 2,
          y0 = r * k,
          x1 = x0,
          y1 = r * k + r,
          x2 = -x1,
          y2 = y1;
      context.moveTo(x0, y0);
      context.lineTo(x1, y1);
      context.lineTo(x2, y2);
      context.lineTo(c$2 * x0 - s * y0, s * x0 + c$2 * y0);
      context.lineTo(c$2 * x1 - s * y1, s * x1 + c$2 * y1);
      context.lineTo(c$2 * x2 - s * y2, s * x2 + c$2 * y2);
      context.lineTo(c$2 * x0 + s * y0, c$2 * y0 - s * x0);
      context.lineTo(c$2 * x1 + s * y1, c$2 * y1 - s * x1);
      context.lineTo(c$2 * x2 + s * y2, c$2 * y2 - s * x2);
      context.closePath();
    }
  };

  var symbols = [circle$2, cross$2, diamond, square, star, triangle, wye];
  function symbol () {
    var type = constant$b(circle$2),
        size = constant$b(64),
        context = null;

    function symbol() {
      var buffer;
      if (!context) context = buffer = path();
      type.apply(this, arguments).draw(context, +size.apply(this, arguments));
      if (buffer) return context = null, buffer + "" || null;
    }

    symbol.type = function (_) {
      return arguments.length ? (type = typeof _ === "function" ? _ : constant$b(_), symbol) : type;
    };

    symbol.size = function (_) {
      return arguments.length ? (size = typeof _ === "function" ? _ : constant$b(+_), symbol) : size;
    };

    symbol.context = function (_) {
      return arguments.length ? (context = _ == null ? null : _, symbol) : context;
    };

    return symbol;
  }

  function noop$3 () {}

  function _point(that, x, y) {
    that._context.bezierCurveTo((2 * that._x0 + that._x1) / 3, (2 * that._y0 + that._y1) / 3, (that._x0 + 2 * that._x1) / 3, (that._y0 + 2 * that._y1) / 3, (that._x0 + 4 * that._x1 + x) / 6, (that._y0 + 4 * that._y1 + y) / 6);
  }
  function Basis(context) {
    this._context = context;
  }
  Basis.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._y0 = this._y1 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 3:
          _point(this, this._x1, this._y1);

        // proceed

        case 2:
          this._context.lineTo(this._x1, this._y1);

          break;
      }

      if (this._line || this._line !== 0 && this._point === 1) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
          break;

        case 1:
          this._point = 2;
          break;

        case 2:
          this._point = 3;

          this._context.lineTo((5 * this._x0 + this._x1) / 6, (5 * this._y0 + this._y1) / 6);

        // proceed

        default:
          _point(this, x, y);

          break;
      }

      this._x0 = this._x1, this._x1 = x;
      this._y0 = this._y1, this._y1 = y;
    }
  };
  function basis$2 (context) {
    return new Basis(context);
  }

  function BasisClosed(context) {
    this._context = context;
  }

  BasisClosed.prototype = {
    areaStart: noop$3,
    areaEnd: noop$3,
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._x3 = this._x4 = this._y0 = this._y1 = this._y2 = this._y3 = this._y4 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 1:
          {
            this._context.moveTo(this._x2, this._y2);

            this._context.closePath();

            break;
          }

        case 2:
          {
            this._context.moveTo((this._x2 + 2 * this._x3) / 3, (this._y2 + 2 * this._y3) / 3);

            this._context.lineTo((this._x3 + 2 * this._x2) / 3, (this._y3 + 2 * this._y2) / 3);

            this._context.closePath();

            break;
          }

        case 3:
          {
            this.point(this._x2, this._y2);
            this.point(this._x3, this._y3);
            this.point(this._x4, this._y4);
            break;
          }
      }
    },
    point: function point$$1(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          this._x2 = x, this._y2 = y;
          break;

        case 1:
          this._point = 2;
          this._x3 = x, this._y3 = y;
          break;

        case 2:
          this._point = 3;
          this._x4 = x, this._y4 = y;

          this._context.moveTo((this._x0 + 4 * this._x1 + x) / 6, (this._y0 + 4 * this._y1 + y) / 6);

          break;

        default:
          _point(this, x, y);

          break;
      }

      this._x0 = this._x1, this._x1 = x;
      this._y0 = this._y1, this._y1 = y;
    }
  };
  function basisClosed$1 (context) {
    return new BasisClosed(context);
  }

  function BasisOpen(context) {
    this._context = context;
  }

  BasisOpen.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._y0 = this._y1 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._line || this._line !== 0 && this._point === 3) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point$$1(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          break;

        case 1:
          this._point = 2;
          break;

        case 2:
          this._point = 3;
          var x0 = (this._x0 + 4 * this._x1 + x) / 6,
              y0 = (this._y0 + 4 * this._y1 + y) / 6;
          this._line ? this._context.lineTo(x0, y0) : this._context.moveTo(x0, y0);
          break;

        case 3:
          this._point = 4;
        // proceed

        default:
          _point(this, x, y);

          break;
      }

      this._x0 = this._x1, this._x1 = x;
      this._y0 = this._y1, this._y1 = y;
    }
  };
  function basisOpen (context) {
    return new BasisOpen(context);
  }

  function Bundle(context, beta) {
    this._basis = new Basis(context);
    this._beta = beta;
  }

  Bundle.prototype = {
    lineStart: function lineStart() {
      this._x = [];
      this._y = [];

      this._basis.lineStart();
    },
    lineEnd: function lineEnd() {
      var x = this._x,
          y = this._y,
          j = x.length - 1;

      if (j > 0) {
        var x0 = x[0],
            y0 = y[0],
            dx = x[j] - x0,
            dy = y[j] - y0,
            i = -1,
            t;

        while (++i <= j) {
          t = i / j;

          this._basis.point(this._beta * x[i] + (1 - this._beta) * (x0 + t * dx), this._beta * y[i] + (1 - this._beta) * (y0 + t * dy));
        }
      }

      this._x = this._y = null;

      this._basis.lineEnd();
    },
    point: function point(x, y) {
      this._x.push(+x);

      this._y.push(+y);
    }
  };
  var bundle = (function custom(beta) {
    function bundle(context) {
      return beta === 1 ? new Basis(context) : new Bundle(context, beta);
    }

    bundle.beta = function (beta) {
      return custom(+beta);
    };

    return bundle;
  })(0.85);

  function _point$1(that, x, y) {
    that._context.bezierCurveTo(that._x1 + that._k * (that._x2 - that._x0), that._y1 + that._k * (that._y2 - that._y0), that._x2 + that._k * (that._x1 - x), that._y2 + that._k * (that._y1 - y), that._x2, that._y2);
  }
  function Cardinal(context, tension) {
    this._context = context;
    this._k = (1 - tension) / 6;
  }
  Cardinal.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._y0 = this._y1 = this._y2 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 2:
          this._context.lineTo(this._x2, this._y2);

          break;

        case 3:
          _point$1(this, this._x1, this._y1);

          break;
      }

      if (this._line || this._line !== 0 && this._point === 1) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
          break;

        case 1:
          this._point = 2;
          this._x1 = x, this._y1 = y;
          break;

        case 2:
          this._point = 3;
        // proceed

        default:
          _point$1(this, x, y);

          break;
      }

      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
    }
  };
  var cardinal = (function custom(tension) {
    function cardinal(context) {
      return new Cardinal(context, tension);
    }

    cardinal.tension = function (tension) {
      return custom(+tension);
    };

    return cardinal;
  })(0);

  function CardinalClosed(context, tension) {
    this._context = context;
    this._k = (1 - tension) / 6;
  }
  CardinalClosed.prototype = {
    areaStart: noop$3,
    areaEnd: noop$3,
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._x3 = this._x4 = this._x5 = this._y0 = this._y1 = this._y2 = this._y3 = this._y4 = this._y5 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 1:
          {
            this._context.moveTo(this._x3, this._y3);

            this._context.closePath();

            break;
          }

        case 2:
          {
            this._context.lineTo(this._x3, this._y3);

            this._context.closePath();

            break;
          }

        case 3:
          {
            this.point(this._x3, this._y3);
            this.point(this._x4, this._y4);
            this.point(this._x5, this._y5);
            break;
          }
      }
    },
    point: function point$$1(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          this._x3 = x, this._y3 = y;
          break;

        case 1:
          this._point = 2;

          this._context.moveTo(this._x4 = x, this._y4 = y);

          break;

        case 2:
          this._point = 3;
          this._x5 = x, this._y5 = y;
          break;

        default:
          _point$1(this, x, y);

          break;
      }

      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
    }
  };
  var cardinalClosed = (function custom(tension) {
    function cardinal$$1(context) {
      return new CardinalClosed(context, tension);
    }

    cardinal$$1.tension = function (tension) {
      return custom(+tension);
    };

    return cardinal$$1;
  })(0);

  function CardinalOpen(context, tension) {
    this._context = context;
    this._k = (1 - tension) / 6;
  }
  CardinalOpen.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._y0 = this._y1 = this._y2 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._line || this._line !== 0 && this._point === 3) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point$$1(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          break;

        case 1:
          this._point = 2;
          break;

        case 2:
          this._point = 3;
          this._line ? this._context.lineTo(this._x2, this._y2) : this._context.moveTo(this._x2, this._y2);
          break;

        case 3:
          this._point = 4;
        // proceed

        default:
          _point$1(this, x, y);

          break;
      }

      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
    }
  };
  var cardinalOpen = (function custom(tension) {
    function cardinal$$1(context) {
      return new CardinalOpen(context, tension);
    }

    cardinal$$1.tension = function (tension) {
      return custom(+tension);
    };

    return cardinal$$1;
  })(0);

  function _point$2(that, x, y) {
    var x1 = that._x1,
        y1 = that._y1,
        x2 = that._x2,
        y2 = that._y2;

    if (that._l01_a > epsilon$3) {
      var a = 2 * that._l01_2a + 3 * that._l01_a * that._l12_a + that._l12_2a,
          n = 3 * that._l01_a * (that._l01_a + that._l12_a);
      x1 = (x1 * a - that._x0 * that._l12_2a + that._x2 * that._l01_2a) / n;
      y1 = (y1 * a - that._y0 * that._l12_2a + that._y2 * that._l01_2a) / n;
    }

    if (that._l23_a > epsilon$3) {
      var b = 2 * that._l23_2a + 3 * that._l23_a * that._l12_a + that._l12_2a,
          m = 3 * that._l23_a * (that._l23_a + that._l12_a);
      x2 = (x2 * b + that._x1 * that._l23_2a - x * that._l12_2a) / m;
      y2 = (y2 * b + that._y1 * that._l23_2a - y * that._l12_2a) / m;
    }

    that._context.bezierCurveTo(x1, y1, x2, y2, that._x2, that._y2);
  }

  function CatmullRom(context, alpha) {
    this._context = context;
    this._alpha = alpha;
  }

  CatmullRom.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._y0 = this._y1 = this._y2 = NaN;
      this._l01_a = this._l12_a = this._l23_a = this._l01_2a = this._l12_2a = this._l23_2a = this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 2:
          this._context.lineTo(this._x2, this._y2);

          break;

        case 3:
          this.point(this._x2, this._y2);
          break;
      }

      if (this._line || this._line !== 0 && this._point === 1) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point(x, y) {
      x = +x, y = +y;

      if (this._point) {
        var x23 = this._x2 - x,
            y23 = this._y2 - y;
        this._l23_a = Math.sqrt(this._l23_2a = Math.pow(x23 * x23 + y23 * y23, this._alpha));
      }

      switch (this._point) {
        case 0:
          this._point = 1;
          this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
          break;

        case 1:
          this._point = 2;
          break;

        case 2:
          this._point = 3;
        // proceed

        default:
          _point$2(this, x, y);

          break;
      }

      this._l01_a = this._l12_a, this._l12_a = this._l23_a;
      this._l01_2a = this._l12_2a, this._l12_2a = this._l23_2a;
      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
    }
  };
  var catmullRom = (function custom(alpha) {
    function catmullRom(context) {
      return alpha ? new CatmullRom(context, alpha) : new Cardinal(context, 0);
    }

    catmullRom.alpha = function (alpha) {
      return custom(+alpha);
    };

    return catmullRom;
  })(0.5);

  function CatmullRomClosed(context, alpha) {
    this._context = context;
    this._alpha = alpha;
  }

  CatmullRomClosed.prototype = {
    areaStart: noop$3,
    areaEnd: noop$3,
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._x3 = this._x4 = this._x5 = this._y0 = this._y1 = this._y2 = this._y3 = this._y4 = this._y5 = NaN;
      this._l01_a = this._l12_a = this._l23_a = this._l01_2a = this._l12_2a = this._l23_2a = this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 1:
          {
            this._context.moveTo(this._x3, this._y3);

            this._context.closePath();

            break;
          }

        case 2:
          {
            this._context.lineTo(this._x3, this._y3);

            this._context.closePath();

            break;
          }

        case 3:
          {
            this.point(this._x3, this._y3);
            this.point(this._x4, this._y4);
            this.point(this._x5, this._y5);
            break;
          }
      }
    },
    point: function point$$1(x, y) {
      x = +x, y = +y;

      if (this._point) {
        var x23 = this._x2 - x,
            y23 = this._y2 - y;
        this._l23_a = Math.sqrt(this._l23_2a = Math.pow(x23 * x23 + y23 * y23, this._alpha));
      }

      switch (this._point) {
        case 0:
          this._point = 1;
          this._x3 = x, this._y3 = y;
          break;

        case 1:
          this._point = 2;

          this._context.moveTo(this._x4 = x, this._y4 = y);

          break;

        case 2:
          this._point = 3;
          this._x5 = x, this._y5 = y;
          break;

        default:
          _point$2(this, x, y);

          break;
      }

      this._l01_a = this._l12_a, this._l12_a = this._l23_a;
      this._l01_2a = this._l12_2a, this._l12_2a = this._l23_2a;
      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
    }
  };
  var catmullRomClosed = (function custom(alpha) {
    function catmullRom$$1(context) {
      return alpha ? new CatmullRomClosed(context, alpha) : new CardinalClosed(context, 0);
    }

    catmullRom$$1.alpha = function (alpha) {
      return custom(+alpha);
    };

    return catmullRom$$1;
  })(0.5);

  function CatmullRomOpen(context, alpha) {
    this._context = context;
    this._alpha = alpha;
  }

  CatmullRomOpen.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._x2 = this._y0 = this._y1 = this._y2 = NaN;
      this._l01_a = this._l12_a = this._l23_a = this._l01_2a = this._l12_2a = this._l23_2a = this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._line || this._line !== 0 && this._point === 3) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point$$1(x, y) {
      x = +x, y = +y;

      if (this._point) {
        var x23 = this._x2 - x,
            y23 = this._y2 - y;
        this._l23_a = Math.sqrt(this._l23_2a = Math.pow(x23 * x23 + y23 * y23, this._alpha));
      }

      switch (this._point) {
        case 0:
          this._point = 1;
          break;

        case 1:
          this._point = 2;
          break;

        case 2:
          this._point = 3;
          this._line ? this._context.lineTo(this._x2, this._y2) : this._context.moveTo(this._x2, this._y2);
          break;

        case 3:
          this._point = 4;
        // proceed

        default:
          _point$2(this, x, y);

          break;
      }

      this._l01_a = this._l12_a, this._l12_a = this._l23_a;
      this._l01_2a = this._l12_2a, this._l12_2a = this._l23_2a;
      this._x0 = this._x1, this._x1 = this._x2, this._x2 = x;
      this._y0 = this._y1, this._y1 = this._y2, this._y2 = y;
    }
  };
  var catmullRomOpen = (function custom(alpha) {
    function catmullRom$$1(context) {
      return alpha ? new CatmullRomOpen(context, alpha) : new CardinalOpen(context, 0);
    }

    catmullRom$$1.alpha = function (alpha) {
      return custom(+alpha);
    };

    return catmullRom$$1;
  })(0.5);

  function LinearClosed(context) {
    this._context = context;
  }

  LinearClosed.prototype = {
    areaStart: noop$3,
    areaEnd: noop$3,
    lineStart: function lineStart() {
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (this._point) this._context.closePath();
    },
    point: function point(x, y) {
      x = +x, y = +y;
      if (this._point) this._context.lineTo(x, y);else this._point = 1, this._context.moveTo(x, y);
    }
  };
  function linearClosed (context) {
    return new LinearClosed(context);
  }

  function sign$1(x) {
    return x < 0 ? -1 : 1;
  } // Calculate the slopes of the tangents (Hermite-type interpolation) based on
  // the following paper: Steffen, M. 1990. A Simple Method for Monotonic
  // Interpolation in One Dimension. Astronomy and Astrophysics, Vol. 239, NO.
  // NOV(II), P. 443, 1990.


  function slope3(that, x2, y2) {
    var h0 = that._x1 - that._x0,
        h1 = x2 - that._x1,
        s0 = (that._y1 - that._y0) / (h0 || h1 < 0 && -0),
        s1 = (y2 - that._y1) / (h1 || h0 < 0 && -0),
        p = (s0 * h1 + s1 * h0) / (h0 + h1);
    return (sign$1(s0) + sign$1(s1)) * Math.min(Math.abs(s0), Math.abs(s1), 0.5 * Math.abs(p)) || 0;
  } // Calculate a one-sided slope.


  function slope2(that, t) {
    var h = that._x1 - that._x0;
    return h ? (3 * (that._y1 - that._y0) / h - t) / 2 : t;
  } // According to https://en.wikipedia.org/wiki/Cubic_Hermite_spline#Representations
  // "you can express cubic Hermite interpolation in terms of cubic BГ©zier curves
  // with respect to the four values p0, p0 + m0 / 3, p1 - m1 / 3, p1".


  function _point$3(that, t0, t1) {
    var x0 = that._x0,
        y0 = that._y0,
        x1 = that._x1,
        y1 = that._y1,
        dx = (x1 - x0) / 3;

    that._context.bezierCurveTo(x0 + dx, y0 + dx * t0, x1 - dx, y1 - dx * t1, x1, y1);
  }

  function MonotoneX(context) {
    this._context = context;
  }

  MonotoneX.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x0 = this._x1 = this._y0 = this._y1 = this._t0 = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      switch (this._point) {
        case 2:
          this._context.lineTo(this._x1, this._y1);

          break;

        case 3:
          _point$3(this, this._t0, slope2(this, this._t0));

          break;
      }

      if (this._line || this._line !== 0 && this._point === 1) this._context.closePath();
      this._line = 1 - this._line;
    },
    point: function point(x, y) {
      var t1 = NaN;
      x = +x, y = +y;
      if (x === this._x1 && y === this._y1) return; // Ignore coincident points.

      switch (this._point) {
        case 0:
          this._point = 1;
          this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
          break;

        case 1:
          this._point = 2;
          break;

        case 2:
          this._point = 3;

          _point$3(this, slope2(this, t1 = slope3(this, x, y)), t1);

          break;

        default:
          _point$3(this, this._t0, t1 = slope3(this, x, y));

          break;
      }

      this._x0 = this._x1, this._x1 = x;
      this._y0 = this._y1, this._y1 = y;
      this._t0 = t1;
    }
  };

  function MonotoneY(context) {
    this._context = new ReflectContext(context);
  }

  (MonotoneY.prototype = Object.create(MonotoneX.prototype)).point = function (x, y) {
    MonotoneX.prototype.point.call(this, y, x);
  };

  function ReflectContext(context) {
    this._context = context;
  }

  ReflectContext.prototype = {
    moveTo: function moveTo(x, y) {
      this._context.moveTo(y, x);
    },
    closePath: function closePath() {
      this._context.closePath();
    },
    lineTo: function lineTo(x, y) {
      this._context.lineTo(y, x);
    },
    bezierCurveTo: function bezierCurveTo(x1, y1, x2, y2, x, y) {
      this._context.bezierCurveTo(y1, x1, y2, x2, y, x);
    }
  };
  function monotoneX(context) {
    return new MonotoneX(context);
  }
  function monotoneY(context) {
    return new MonotoneY(context);
  }

  function Natural(context) {
    this._context = context;
  }

  Natural.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x = [];
      this._y = [];
    },
    lineEnd: function lineEnd() {
      var x = this._x,
          y = this._y,
          n = x.length;

      if (n) {
        this._line ? this._context.lineTo(x[0], y[0]) : this._context.moveTo(x[0], y[0]);

        if (n === 2) {
          this._context.lineTo(x[1], y[1]);
        } else {
          var px = controlPoints(x),
              py = controlPoints(y);

          for (var i0 = 0, i1 = 1; i1 < n; ++i0, ++i1) {
            this._context.bezierCurveTo(px[0][i0], py[0][i0], px[1][i0], py[1][i0], x[i1], y[i1]);
          }
        }
      }

      if (this._line || this._line !== 0 && n === 1) this._context.closePath();
      this._line = 1 - this._line;
      this._x = this._y = null;
    },
    point: function point(x, y) {
      this._x.push(+x);

      this._y.push(+y);
    }
  }; // See https://www.particleincell.com/2012/bezier-splines/ for derivation.

  function controlPoints(x) {
    var i,
        n = x.length - 1,
        m,
        a = new Array(n),
        b = new Array(n),
        r = new Array(n);
    a[0] = 0, b[0] = 2, r[0] = x[0] + 2 * x[1];

    for (i = 1; i < n - 1; ++i) {
      a[i] = 1, b[i] = 4, r[i] = 4 * x[i] + 2 * x[i + 1];
    }

    a[n - 1] = 2, b[n - 1] = 7, r[n - 1] = 8 * x[n - 1] + x[n];

    for (i = 1; i < n; ++i) {
      m = a[i] / b[i - 1], b[i] -= m, r[i] -= m * r[i - 1];
    }

    a[n - 1] = r[n - 1] / b[n - 1];

    for (i = n - 2; i >= 0; --i) {
      a[i] = (r[i] - a[i + 1]) / b[i];
    }

    b[n - 1] = (x[n] + a[n - 1]) / 2;

    for (i = 0; i < n - 1; ++i) {
      b[i] = 2 * x[i + 1] - a[i + 1];
    }

    return [a, b];
  }

  function natural (context) {
    return new Natural(context);
  }

  function Step(context, t) {
    this._context = context;
    this._t = t;
  }

  Step.prototype = {
    areaStart: function areaStart() {
      this._line = 0;
    },
    areaEnd: function areaEnd() {
      this._line = NaN;
    },
    lineStart: function lineStart() {
      this._x = this._y = NaN;
      this._point = 0;
    },
    lineEnd: function lineEnd() {
      if (0 < this._t && this._t < 1 && this._point === 2) this._context.lineTo(this._x, this._y);
      if (this._line || this._line !== 0 && this._point === 1) this._context.closePath();
      if (this._line >= 0) this._t = 1 - this._t, this._line = 1 - this._line;
    },
    point: function point(x, y) {
      x = +x, y = +y;

      switch (this._point) {
        case 0:
          this._point = 1;
          this._line ? this._context.lineTo(x, y) : this._context.moveTo(x, y);
          break;

        case 1:
          this._point = 2;
        // proceed

        default:
          {
            if (this._t <= 0) {
              this._context.lineTo(this._x, y);

              this._context.lineTo(x, y);
            } else {
              var x1 = this._x * (1 - this._t) + x * this._t;

              this._context.lineTo(x1, this._y);

              this._context.lineTo(x1, y);
            }

            break;
          }
      }

      this._x = x, this._y = y;
    }
  };
  function step (context) {
    return new Step(context, 0.5);
  }
  function stepBefore(context) {
    return new Step(context, 0);
  }
  function stepAfter(context) {
    return new Step(context, 1);
  }

  function none$1 (series, order) {
    if (!((n = series.length) > 1)) return;

    for (var i = 1, j, s0, s1 = series[order[0]], n, m = s1.length; i < n; ++i) {
      s0 = s1, s1 = series[order[i]];

      for (j = 0; j < m; ++j) {
        s1[j][1] += s1[j][0] = isNaN(s0[j][1]) ? s0[j][0] : s0[j][1];
      }
    }
  }

  function none$2 (series) {
    var n = series.length,
        o = new Array(n);

    while (--n >= 0) {
      o[n] = n;
    }

    return o;
  }

  function stackValue(d, key) {
    return d[key];
  }

  function stack () {
    var keys = constant$b([]),
        order = none$2,
        offset = none$1,
        value = stackValue;

    function stack(data) {
      var kz = keys.apply(this, arguments),
          i,
          m = data.length,
          n = kz.length,
          sz = new Array(n),
          oz;

      for (i = 0; i < n; ++i) {
        for (var ki = kz[i], si = sz[i] = new Array(m), j = 0, sij; j < m; ++j) {
          si[j] = sij = [0, +value(data[j], ki, j, data)];
          sij.data = data[j];
        }

        si.key = ki;
      }

      for (i = 0, oz = order(sz); i < n; ++i) {
        sz[oz[i]].index = i;
      }

      offset(sz, oz);
      return sz;
    }

    stack.keys = function (_) {
      return arguments.length ? (keys = typeof _ === "function" ? _ : constant$b(slice$6.call(_)), stack) : keys;
    };

    stack.value = function (_) {
      return arguments.length ? (value = typeof _ === "function" ? _ : constant$b(+_), stack) : value;
    };

    stack.order = function (_) {
      return arguments.length ? (order = _ == null ? none$2 : typeof _ === "function" ? _ : constant$b(slice$6.call(_)), stack) : order;
    };

    stack.offset = function (_) {
      return arguments.length ? (offset = _ == null ? none$1 : _, stack) : offset;
    };

    return stack;
  }

  function expand (series, order) {
    if (!((n = series.length) > 0)) return;

    for (var i, n, j = 0, m = series[0].length, y; j < m; ++j) {
      for (y = i = 0; i < n; ++i) {
        y += series[i][j][1] || 0;
      }

      if (y) for (i = 0; i < n; ++i) {
        series[i][j][1] /= y;
      }
    }

    none$1(series, order);
  }

  function diverging$1 (series, order) {
    if (!((n = series.length) > 0)) return;

    for (var i, j = 0, d, dy, yp, yn, n, m = series[order[0]].length; j < m; ++j) {
      for (yp = yn = 0, i = 0; i < n; ++i) {
        if ((dy = (d = series[order[i]][j])[1] - d[0]) >= 0) {
          d[0] = yp, d[1] = yp += dy;
        } else if (dy < 0) {
          d[1] = yn, d[0] = yn += dy;
        } else {
          d[0] = yp;
        }
      }
    }
  }

  function silhouette (series, order) {
    if (!((n = series.length) > 0)) return;

    for (var j = 0, s0 = series[order[0]], n, m = s0.length; j < m; ++j) {
      for (var i = 0, y = 0; i < n; ++i) {
        y += series[i][j][1] || 0;
      }

      s0[j][1] += s0[j][0] = -y / 2;
    }

    none$1(series, order);
  }

  function wiggle (series, order) {
    if (!((n = series.length) > 0) || !((m = (s0 = series[order[0]]).length) > 0)) return;

    for (var y = 0, j = 1, s0, m, n; j < m; ++j) {
      for (var i = 0, s1 = 0, s2 = 0; i < n; ++i) {
        var si = series[order[i]],
            sij0 = si[j][1] || 0,
            sij1 = si[j - 1][1] || 0,
            s3 = (sij0 - sij1) / 2;

        for (var k = 0; k < i; ++k) {
          var sk = series[order[k]],
              skj0 = sk[j][1] || 0,
              skj1 = sk[j - 1][1] || 0;
          s3 += skj0 - skj1;
        }

        s1 += sij0, s2 += s3 * sij0;
      }

      s0[j - 1][1] += s0[j - 1][0] = y;
      if (s1) y -= s2 / s1;
    }

    s0[j - 1][1] += s0[j - 1][0] = y;
    none$1(series, order);
  }

  function appearance (series) {
    var peaks = series.map(peak);
    return none$2(series).sort(function (a, b) {
      return peaks[a] - peaks[b];
    });
  }

  function peak(series) {
    var i = -1,
        j = 0,
        n = series.length,
        vi,
        vj = -Infinity;

    while (++i < n) {
      if ((vi = +series[i][1]) > vj) vj = vi, j = i;
    }

    return j;
  }

  function ascending$3 (series) {
    var sums = series.map(sum$2);
    return none$2(series).sort(function (a, b) {
      return sums[a] - sums[b];
    });
  }
  function sum$2(series) {
    var s = 0,
        i = -1,
        n = series.length,
        v;

    while (++i < n) {
      if (v = +series[i][1]) s += v;
    }

    return s;
  }

  function descending$2 (series) {
    return ascending$3(series).reverse();
  }

  function insideOut (series) {
    var n = series.length,
        i,
        j,
        sums = series.map(sum$2),
        order = appearance(series),
        top = 0,
        bottom = 0,
        tops = [],
        bottoms = [];

    for (i = 0; i < n; ++i) {
      j = order[i];

      if (top < bottom) {
        top += sums[j];
        tops.push(j);
      } else {
        bottom += sums[j];
        bottoms.push(j);
      }
    }

    return bottoms.reverse().concat(tops);
  }

  function reverse (series) {
    return none$2(series).reverse();
  }

  function constant$c (x) {
    return function () {
      return x;
    };
  }

  function x$4(d) {
    return d[0];
  }
  function y$4(d) {
    return d[1];
  }

  function RedBlackTree() {
    this._ = null; // root node
  }

  function RedBlackNode(node) {
    node.U = // parent node
    node.C = // color - true for red, false for black
    node.L = // left node
    node.R = // right node
    node.P = // previous node
    node.N = null; // next node
  }
  RedBlackTree.prototype = {
    constructor: RedBlackTree,
    insert: function insert(after, node) {
      var parent, grandpa, uncle;

      if (after) {
        node.P = after;
        node.N = after.N;
        if (after.N) after.N.P = node;
        after.N = node;

        if (after.R) {
          after = after.R;

          while (after.L) {
            after = after.L;
          }

          after.L = node;
        } else {
          after.R = node;
        }

        parent = after;
      } else if (this._) {
        after = RedBlackFirst(this._);
        node.P = null;
        node.N = after;
        after.P = after.L = node;
        parent = after;
      } else {
        node.P = node.N = null;
        this._ = node;
        parent = null;
      }

      node.L = node.R = null;
      node.U = parent;
      node.C = true;
      after = node;

      while (parent && parent.C) {
        grandpa = parent.U;

        if (parent === grandpa.L) {
          uncle = grandpa.R;

          if (uncle && uncle.C) {
            parent.C = uncle.C = false;
            grandpa.C = true;
            after = grandpa;
          } else {
            if (after === parent.R) {
              RedBlackRotateLeft(this, parent);
              after = parent;
              parent = after.U;
            }

            parent.C = false;
            grandpa.C = true;
            RedBlackRotateRight(this, grandpa);
          }
        } else {
          uncle = grandpa.L;

          if (uncle && uncle.C) {
            parent.C = uncle.C = false;
            grandpa.C = true;
            after = grandpa;
          } else {
            if (after === parent.L) {
              RedBlackRotateRight(this, parent);
              after = parent;
              parent = after.U;
            }

            parent.C = false;
            grandpa.C = true;
            RedBlackRotateLeft(this, grandpa);
          }
        }

        parent = after.U;
      }

      this._.C = false;
    },
    remove: function remove(node) {
      if (node.N) node.N.P = node.P;
      if (node.P) node.P.N = node.N;
      node.N = node.P = null;
      var parent = node.U,
          sibling,
          left = node.L,
          right = node.R,
          next,
          red;
      if (!left) next = right;else if (!right) next = left;else next = RedBlackFirst(right);

      if (parent) {
        if (parent.L === node) parent.L = next;else parent.R = next;
      } else {
        this._ = next;
      }

      if (left && right) {
        red = next.C;
        next.C = node.C;
        next.L = left;
        left.U = next;

        if (next !== right) {
          parent = next.U;
          next.U = node.U;
          node = next.R;
          parent.L = node;
          next.R = right;
          right.U = next;
        } else {
          next.U = parent;
          parent = next;
          node = next.R;
        }
      } else {
        red = node.C;
        node = next;
      }

      if (node) node.U = parent;
      if (red) return;

      if (node && node.C) {
        node.C = false;
        return;
      }

      do {
        if (node === this._) break;

        if (node === parent.L) {
          sibling = parent.R;

          if (sibling.C) {
            sibling.C = false;
            parent.C = true;
            RedBlackRotateLeft(this, parent);
            sibling = parent.R;
          }

          if (sibling.L && sibling.L.C || sibling.R && sibling.R.C) {
            if (!sibling.R || !sibling.R.C) {
              sibling.L.C = false;
              sibling.C = true;
              RedBlackRotateRight(this, sibling);
              sibling = parent.R;
            }

            sibling.C = parent.C;
            parent.C = sibling.R.C = false;
            RedBlackRotateLeft(this, parent);
            node = this._;
            break;
          }
        } else {
          sibling = parent.L;

          if (sibling.C) {
            sibling.C = false;
            parent.C = true;
            RedBlackRotateRight(this, parent);
            sibling = parent.L;
          }

          if (sibling.L && sibling.L.C || sibling.R && sibling.R.C) {
            if (!sibling.L || !sibling.L.C) {
              sibling.R.C = false;
              sibling.C = true;
              RedBlackRotateLeft(this, sibling);
              sibling = parent.L;
            }

            sibling.C = parent.C;
            parent.C = sibling.L.C = false;
            RedBlackRotateRight(this, parent);
            node = this._;
            break;
          }
        }

        sibling.C = true;
        node = parent;
        parent = parent.U;
      } while (!node.C);

      if (node) node.C = false;
    }
  };

  function RedBlackRotateLeft(tree, node) {
    var p = node,
        q = node.R,
        parent = p.U;

    if (parent) {
      if (parent.L === p) parent.L = q;else parent.R = q;
    } else {
      tree._ = q;
    }

    q.U = parent;
    p.U = q;
    p.R = q.L;
    if (p.R) p.R.U = p;
    q.L = p;
  }

  function RedBlackRotateRight(tree, node) {
    var p = node,
        q = node.L,
        parent = p.U;

    if (parent) {
      if (parent.L === p) parent.L = q;else parent.R = q;
    } else {
      tree._ = q;
    }

    q.U = parent;
    p.U = q;
    p.L = q.R;
    if (p.L) p.L.U = p;
    q.R = p;
  }

  function RedBlackFirst(node) {
    while (node.L) {
      node = node.L;
    }

    return node;
  }

  function createEdge(left, right, v0, v1) {
    var edge = [null, null],
        index = edges.push(edge) - 1;
    edge.left = left;
    edge.right = right;
    if (v0) setEdgeEnd(edge, left, right, v0);
    if (v1) setEdgeEnd(edge, right, left, v1);
    cells[left.index].halfedges.push(index);
    cells[right.index].halfedges.push(index);
    return edge;
  }
  function createBorderEdge(left, v0, v1) {
    var edge = [v0, v1];
    edge.left = left;
    return edge;
  }
  function setEdgeEnd(edge, left, right, vertex) {
    if (!edge[0] && !edge[1]) {
      edge[0] = vertex;
      edge.left = left;
      edge.right = right;
    } else if (edge.left === right) {
      edge[1] = vertex;
    } else {
      edge[0] = vertex;
    }
  } // LiangвЂ“Barsky line clipping.

  function clipEdge(edge, x0, y0, x1, y1) {
    var a = edge[0],
        b = edge[1],
        ax = a[0],
        ay = a[1],
        bx = b[0],
        by = b[1],
        t0 = 0,
        t1 = 1,
        dx = bx - ax,
        dy = by - ay,
        r;
    r = x0 - ax;
    if (!dx && r > 0) return;
    r /= dx;

    if (dx < 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    } else if (dx > 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    }

    r = x1 - ax;
    if (!dx && r < 0) return;
    r /= dx;

    if (dx < 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    } else if (dx > 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    }

    r = y0 - ay;
    if (!dy && r > 0) return;
    r /= dy;

    if (dy < 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    } else if (dy > 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    }

    r = y1 - ay;
    if (!dy && r < 0) return;
    r /= dy;

    if (dy < 0) {
      if (r > t1) return;
      if (r > t0) t0 = r;
    } else if (dy > 0) {
      if (r < t0) return;
      if (r < t1) t1 = r;
    }

    if (!(t0 > 0) && !(t1 < 1)) return true; // TODO Better check?

    if (t0 > 0) edge[0] = [ax + t0 * dx, ay + t0 * dy];
    if (t1 < 1) edge[1] = [ax + t1 * dx, ay + t1 * dy];
    return true;
  }

  function connectEdge(edge, x0, y0, x1, y1) {
    var v1 = edge[1];
    if (v1) return true;
    var v0 = edge[0],
        left = edge.left,
        right = edge.right,
        lx = left[0],
        ly = left[1],
        rx = right[0],
        ry = right[1],
        fx = (lx + rx) / 2,
        fy = (ly + ry) / 2,
        fm,
        fb;

    if (ry === ly) {
      if (fx < x0 || fx >= x1) return;

      if (lx > rx) {
        if (!v0) v0 = [fx, y0];else if (v0[1] >= y1) return;
        v1 = [fx, y1];
      } else {
        if (!v0) v0 = [fx, y1];else if (v0[1] < y0) return;
        v1 = [fx, y0];
      }
    } else {
      fm = (lx - rx) / (ry - ly);
      fb = fy - fm * fx;

      if (fm < -1 || fm > 1) {
        if (lx > rx) {
          if (!v0) v0 = [(y0 - fb) / fm, y0];else if (v0[1] >= y1) return;
          v1 = [(y1 - fb) / fm, y1];
        } else {
          if (!v0) v0 = [(y1 - fb) / fm, y1];else if (v0[1] < y0) return;
          v1 = [(y0 - fb) / fm, y0];
        }
      } else {
        if (ly < ry) {
          if (!v0) v0 = [x0, fm * x0 + fb];else if (v0[0] >= x1) return;
          v1 = [x1, fm * x1 + fb];
        } else {
          if (!v0) v0 = [x1, fm * x1 + fb];else if (v0[0] < x0) return;
          v1 = [x0, fm * x0 + fb];
        }
      }
    }

    edge[0] = v0;
    edge[1] = v1;
    return true;
  }

  function clipEdges(x0, y0, x1, y1) {
    var i = edges.length,
        edge;

    while (i--) {
      if (!connectEdge(edge = edges[i], x0, y0, x1, y1) || !clipEdge(edge, x0, y0, x1, y1) || !(Math.abs(edge[0][0] - edge[1][0]) > epsilon$4 || Math.abs(edge[0][1] - edge[1][1]) > epsilon$4)) {
        delete edges[i];
      }
    }
  }

  function createCell(site) {
    return cells[site.index] = {
      site: site,
      halfedges: []
    };
  }

  function cellHalfedgeAngle(cell, edge) {
    var site = cell.site,
        va = edge.left,
        vb = edge.right;
    if (site === vb) vb = va, va = site;
    if (vb) return Math.atan2(vb[1] - va[1], vb[0] - va[0]);
    if (site === va) va = edge[1], vb = edge[0];else va = edge[0], vb = edge[1];
    return Math.atan2(va[0] - vb[0], vb[1] - va[1]);
  }

  function cellHalfedgeStart(cell, edge) {
    return edge[+(edge.left !== cell.site)];
  }
  function cellHalfedgeEnd(cell, edge) {
    return edge[+(edge.left === cell.site)];
  }
  function sortCellHalfedges() {
    for (var i = 0, n = cells.length, cell, halfedges, j, m; i < n; ++i) {
      if ((cell = cells[i]) && (m = (halfedges = cell.halfedges).length)) {
        var index = new Array(m),
            array = new Array(m);

        for (j = 0; j < m; ++j) {
          index[j] = j, array[j] = cellHalfedgeAngle(cell, edges[halfedges[j]]);
        }

        index.sort(function (i, j) {
          return array[j] - array[i];
        });

        for (j = 0; j < m; ++j) {
          array[j] = halfedges[index[j]];
        }

        for (j = 0; j < m; ++j) {
          halfedges[j] = array[j];
        }
      }
    }
  }
  function clipCells(x0, y0, x1, y1) {
    var nCells = cells.length,
        iCell,
        cell,
        site,
        iHalfedge,
        halfedges,
        nHalfedges,
        start,
        startX,
        startY,
        end,
        endX,
        endY,
        cover = true;

    for (iCell = 0; iCell < nCells; ++iCell) {
      if (cell = cells[iCell]) {
        site = cell.site;
        halfedges = cell.halfedges;
        iHalfedge = halfedges.length; // Remove any dangling clipped edges.

        while (iHalfedge--) {
          if (!edges[halfedges[iHalfedge]]) {
            halfedges.splice(iHalfedge, 1);
          }
        } // Insert any border edges as necessary.


        iHalfedge = 0, nHalfedges = halfedges.length;

        while (iHalfedge < nHalfedges) {
          end = cellHalfedgeEnd(cell, edges[halfedges[iHalfedge]]), endX = end[0], endY = end[1];
          start = cellHalfedgeStart(cell, edges[halfedges[++iHalfedge % nHalfedges]]), startX = start[0], startY = start[1];

          if (Math.abs(endX - startX) > epsilon$4 || Math.abs(endY - startY) > epsilon$4) {
            halfedges.splice(iHalfedge, 0, edges.push(createBorderEdge(site, end, Math.abs(endX - x0) < epsilon$4 && y1 - endY > epsilon$4 ? [x0, Math.abs(startX - x0) < epsilon$4 ? startY : y1] : Math.abs(endY - y1) < epsilon$4 && x1 - endX > epsilon$4 ? [Math.abs(startY - y1) < epsilon$4 ? startX : x1, y1] : Math.abs(endX - x1) < epsilon$4 && endY - y0 > epsilon$4 ? [x1, Math.abs(startX - x1) < epsilon$4 ? startY : y0] : Math.abs(endY - y0) < epsilon$4 && endX - x0 > epsilon$4 ? [Math.abs(startY - y0) < epsilon$4 ? startX : x0, y0] : null)) - 1);
            ++nHalfedges;
          }
        }

        if (nHalfedges) cover = false;
      }
    } // If there werenвЂ™t any edges, have the closest site cover the extent.
    // It doesnвЂ™t matter which corner of the extent we measure!


    if (cover) {
      var dx,
          dy,
          d2,
          dc = Infinity;

      for (iCell = 0, cover = null; iCell < nCells; ++iCell) {
        if (cell = cells[iCell]) {
          site = cell.site;
          dx = site[0] - x0;
          dy = site[1] - y0;
          d2 = dx * dx + dy * dy;
          if (d2 < dc) dc = d2, cover = cell;
        }
      }

      if (cover) {
        var v00 = [x0, y0],
            v01 = [x0, y1],
            v11 = [x1, y1],
            v10 = [x1, y0];
        cover.halfedges.push(edges.push(createBorderEdge(site = cover.site, v00, v01)) - 1, edges.push(createBorderEdge(site, v01, v11)) - 1, edges.push(createBorderEdge(site, v11, v10)) - 1, edges.push(createBorderEdge(site, v10, v00)) - 1);
      }
    } // Lastly delete any cells with no edges; these were entirely clipped.


    for (iCell = 0; iCell < nCells; ++iCell) {
      if (cell = cells[iCell]) {
        if (!cell.halfedges.length) {
          delete cells[iCell];
        }
      }
    }
  }

  var circlePool = [];
  var firstCircle;

  function Circle() {
    RedBlackNode(this);
    this.x = this.y = this.arc = this.site = this.cy = null;
  }

  function attachCircle(arc) {
    var lArc = arc.P,
        rArc = arc.N;
    if (!lArc || !rArc) return;
    var lSite = lArc.site,
        cSite = arc.site,
        rSite = rArc.site;
    if (lSite === rSite) return;
    var bx = cSite[0],
        by = cSite[1],
        ax = lSite[0] - bx,
        ay = lSite[1] - by,
        cx = rSite[0] - bx,
        cy = rSite[1] - by;
    var d = 2 * (ax * cy - ay * cx);
    if (d >= -epsilon2$2) return;
    var ha = ax * ax + ay * ay,
        hc = cx * cx + cy * cy,
        x = (cy * ha - ay * hc) / d,
        y = (ax * hc - cx * ha) / d;
    var circle = circlePool.pop() || new Circle();
    circle.arc = arc;
    circle.site = cSite;
    circle.x = x + bx;
    circle.y = (circle.cy = y + by) + Math.sqrt(x * x + y * y); // y bottom

    arc.circle = circle;
    var before = null,
        node = circles._;

    while (node) {
      if (circle.y < node.y || circle.y === node.y && circle.x <= node.x) {
        if (node.L) node = node.L;else {
          before = node.P;
          break;
        }
      } else {
        if (node.R) node = node.R;else {
          before = node;
          break;
        }
      }
    }

    circles.insert(before, circle);
    if (!before) firstCircle = circle;
  }
  function detachCircle(arc) {
    var circle = arc.circle;

    if (circle) {
      if (!circle.P) firstCircle = circle.N;
      circles.remove(circle);
      circlePool.push(circle);
      RedBlackNode(circle);
      arc.circle = null;
    }
  }

  var beachPool = [];

  function Beach() {
    RedBlackNode(this);
    this.edge = this.site = this.circle = null;
  }

  function createBeach(site) {
    var beach = beachPool.pop() || new Beach();
    beach.site = site;
    return beach;
  }

  function detachBeach(beach) {
    detachCircle(beach);
    beaches.remove(beach);
    beachPool.push(beach);
    RedBlackNode(beach);
  }

  function removeBeach(beach) {
    var circle = beach.circle,
        x = circle.x,
        y = circle.cy,
        vertex = [x, y],
        previous = beach.P,
        next = beach.N,
        disappearing = [beach];
    detachBeach(beach);
    var lArc = previous;

    while (lArc.circle && Math.abs(x - lArc.circle.x) < epsilon$4 && Math.abs(y - lArc.circle.cy) < epsilon$4) {
      previous = lArc.P;
      disappearing.unshift(lArc);
      detachBeach(lArc);
      lArc = previous;
    }

    disappearing.unshift(lArc);
    detachCircle(lArc);
    var rArc = next;

    while (rArc.circle && Math.abs(x - rArc.circle.x) < epsilon$4 && Math.abs(y - rArc.circle.cy) < epsilon$4) {
      next = rArc.N;
      disappearing.push(rArc);
      detachBeach(rArc);
      rArc = next;
    }

    disappearing.push(rArc);
    detachCircle(rArc);
    var nArcs = disappearing.length,
        iArc;

    for (iArc = 1; iArc < nArcs; ++iArc) {
      rArc = disappearing[iArc];
      lArc = disappearing[iArc - 1];
      setEdgeEnd(rArc.edge, lArc.site, rArc.site, vertex);
    }

    lArc = disappearing[0];
    rArc = disappearing[nArcs - 1];
    rArc.edge = createEdge(lArc.site, rArc.site, null, vertex);
    attachCircle(lArc);
    attachCircle(rArc);
  }
  function addBeach(site) {
    var x = site[0],
        directrix = site[1],
        lArc,
        rArc,
        dxl,
        dxr,
        node = beaches._;

    while (node) {
      dxl = leftBreakPoint(node, directrix) - x;
      if (dxl > epsilon$4) node = node.L;else {
        dxr = x - rightBreakPoint(node, directrix);

        if (dxr > epsilon$4) {
          if (!node.R) {
            lArc = node;
            break;
          }

          node = node.R;
        } else {
          if (dxl > -epsilon$4) {
            lArc = node.P;
            rArc = node;
          } else if (dxr > -epsilon$4) {
            lArc = node;
            rArc = node.N;
          } else {
            lArc = rArc = node;
          }

          break;
        }
      }
    }

    createCell(site);
    var newArc = createBeach(site);
    beaches.insert(lArc, newArc);
    if (!lArc && !rArc) return;

    if (lArc === rArc) {
      detachCircle(lArc);
      rArc = createBeach(lArc.site);
      beaches.insert(newArc, rArc);
      newArc.edge = rArc.edge = createEdge(lArc.site, newArc.site);
      attachCircle(lArc);
      attachCircle(rArc);
      return;
    }

    if (!rArc) {
      // && lArc
      newArc.edge = createEdge(lArc.site, newArc.site);
      return;
    } // else lArc !== rArc


    detachCircle(lArc);
    detachCircle(rArc);
    var lSite = lArc.site,
        ax = lSite[0],
        ay = lSite[1],
        bx = site[0] - ax,
        by = site[1] - ay,
        rSite = rArc.site,
        cx = rSite[0] - ax,
        cy = rSite[1] - ay,
        d = 2 * (bx * cy - by * cx),
        hb = bx * bx + by * by,
        hc = cx * cx + cy * cy,
        vertex = [(cy * hb - by * hc) / d + ax, (bx * hc - cx * hb) / d + ay];
    setEdgeEnd(rArc.edge, lSite, rSite, vertex);
    newArc.edge = createEdge(lSite, site, null, vertex);
    rArc.edge = createEdge(site, rSite, null, vertex);
    attachCircle(lArc);
    attachCircle(rArc);
  }

  function leftBreakPoint(arc, directrix) {
    var site = arc.site,
        rfocx = site[0],
        rfocy = site[1],
        pby2 = rfocy - directrix;
    if (!pby2) return rfocx;
    var lArc = arc.P;
    if (!lArc) return -Infinity;
    site = lArc.site;
    var lfocx = site[0],
        lfocy = site[1],
        plby2 = lfocy - directrix;
    if (!plby2) return lfocx;
    var hl = lfocx - rfocx,
        aby2 = 1 / pby2 - 1 / plby2,
        b = hl / plby2;
    if (aby2) return (-b + Math.sqrt(b * b - 2 * aby2 * (hl * hl / (-2 * plby2) - lfocy + plby2 / 2 + rfocy - pby2 / 2))) / aby2 + rfocx;
    return (rfocx + lfocx) / 2;
  }

  function rightBreakPoint(arc, directrix) {
    var rArc = arc.N;
    if (rArc) return leftBreakPoint(rArc, directrix);
    var site = arc.site;
    return site[1] === directrix ? site[0] : Infinity;
  }

  var epsilon$4 = 1e-6;
  var epsilon2$2 = 1e-12;
  var beaches;
  var cells;
  var circles;
  var edges;

  function triangleArea(a, b, c) {
    return (a[0] - c[0]) * (b[1] - a[1]) - (a[0] - b[0]) * (c[1] - a[1]);
  }

  function lexicographic(a, b) {
    return b[1] - a[1] || b[0] - a[0];
  }

  function Diagram(sites, extent) {
    var site = sites.sort(lexicographic).pop(),
        x,
        y,
        circle;
    edges = [];
    cells = new Array(sites.length);
    beaches = new RedBlackTree();
    circles = new RedBlackTree();

    while (true) {
      circle = firstCircle;

      if (site && (!circle || site[1] < circle.y || site[1] === circle.y && site[0] < circle.x)) {
        if (site[0] !== x || site[1] !== y) {
          addBeach(site);
          x = site[0], y = site[1];
        }

        site = sites.pop();
      } else if (circle) {
        removeBeach(circle.arc);
      } else {
        break;
      }
    }

    sortCellHalfedges();

    if (extent) {
      var x0 = +extent[0][0],
          y0 = +extent[0][1],
          x1 = +extent[1][0],
          y1 = +extent[1][1];
      clipEdges(x0, y0, x1, y1);
      clipCells(x0, y0, x1, y1);
    }

    this.edges = edges;
    this.cells = cells;
    beaches = circles = edges = cells = null;
  }
  Diagram.prototype = {
    constructor: Diagram,
    polygons: function polygons() {
      var edges = this.edges;
      return this.cells.map(function (cell) {
        var polygon = cell.halfedges.map(function (i) {
          return cellHalfedgeStart(cell, edges[i]);
        });
        polygon.data = cell.site.data;
        return polygon;
      });
    },
    triangles: function triangles() {
      var triangles = [],
          edges = this.edges;
      this.cells.forEach(function (cell, i) {
        if (!(m = (halfedges = cell.halfedges).length)) return;
        var site = cell.site,
            halfedges,
            j = -1,
            m,
            s0,
            e1 = edges[halfedges[m - 1]],
            s1 = e1.left === site ? e1.right : e1.left;

        while (++j < m) {
          s0 = s1;
          e1 = edges[halfedges[j]];
          s1 = e1.left === site ? e1.right : e1.left;

          if (s0 && s1 && i < s0.index && i < s1.index && triangleArea(site, s0, s1) < 0) {
            triangles.push([site.data, s0.data, s1.data]);
          }
        }
      });
      return triangles;
    },
    links: function links() {
      return this.edges.filter(function (edge) {
        return edge.right;
      }).map(function (edge) {
        return {
          source: edge.left.data,
          target: edge.right.data
        };
      });
    },
    find: function find(x, y, radius) {
      var that = this,
          i0,
          i1 = that._found || 0,
          n = that.cells.length,
          cell; // Use the previously-found cell, or start with an arbitrary one.

      while (!(cell = that.cells[i1])) {
        if (++i1 >= n) return null;
      }

      var dx = x - cell.site[0],
          dy = y - cell.site[1],
          d2 = dx * dx + dy * dy; // Traverse the half-edges to find a closer cell, if any.

      do {
        cell = that.cells[i0 = i1], i1 = null;
        cell.halfedges.forEach(function (e) {
          var edge = that.edges[e],
              v = edge.left;
          if ((v === cell.site || !v) && !(v = edge.right)) return;
          var vx = x - v[0],
              vy = y - v[1],
              v2 = vx * vx + vy * vy;
          if (v2 < d2) d2 = v2, i1 = v.index;
        });
      } while (i1 !== null);

      that._found = i0;
      return radius == null || d2 <= radius * radius ? cell.site : null;
    }
  };

  function voronoi () {
    var x$$1 = x$4,
        y$$1 = y$4,
        extent = null;

    function voronoi(data) {
      return new Diagram(data.map(function (d, i) {
        var s = [Math.round(x$$1(d, i, data) / epsilon$4) * epsilon$4, Math.round(y$$1(d, i, data) / epsilon$4) * epsilon$4];
        s.index = i;
        s.data = d;
        return s;
      }), extent);
    }

    voronoi.polygons = function (data) {
      return voronoi(data).polygons();
    };

    voronoi.links = function (data) {
      return voronoi(data).links();
    };

    voronoi.triangles = function (data) {
      return voronoi(data).triangles();
    };

    voronoi.x = function (_) {
      return arguments.length ? (x$$1 = typeof _ === "function" ? _ : constant$c(+_), voronoi) : x$$1;
    };

    voronoi.y = function (_) {
      return arguments.length ? (y$$1 = typeof _ === "function" ? _ : constant$c(+_), voronoi) : y$$1;
    };

    voronoi.extent = function (_) {
      return arguments.length ? (extent = _ == null ? null : [[+_[0][0], +_[0][1]], [+_[1][0], +_[1][1]]], voronoi) : extent && [[extent[0][0], extent[0][1]], [extent[1][0], extent[1][1]]];
    };

    voronoi.size = function (_) {
      return arguments.length ? (extent = _ == null ? null : [[0, 0], [+_[0], +_[1]]], voronoi) : extent && [extent[1][0] - extent[0][0], extent[1][1] - extent[0][1]];
    };

    return voronoi;
  }

  function constant$d (x) {
    return function () {
      return x;
    };
  }

  function ZoomEvent(target, type, transform) {
    this.target = target;
    this.type = type;
    this.transform = transform;
  }

  function Transform(k, x, y) {
    this.k = k;
    this.x = x;
    this.y = y;
  }
  Transform.prototype = {
    constructor: Transform,
    scale: function scale(k) {
      return k === 1 ? this : new Transform(this.k * k, this.x, this.y);
    },
    translate: function translate(x, y) {
      return x === 0 & y === 0 ? this : new Transform(this.k, this.x + this.k * x, this.y + this.k * y);
    },
    apply: function apply(point) {
      return [point[0] * this.k + this.x, point[1] * this.k + this.y];
    },
    applyX: function applyX(x) {
      return x * this.k + this.x;
    },
    applyY: function applyY(y) {
      return y * this.k + this.y;
    },
    invert: function invert(location) {
      return [(location[0] - this.x) / this.k, (location[1] - this.y) / this.k];
    },
    invertX: function invertX(x) {
      return (x - this.x) / this.k;
    },
    invertY: function invertY(y) {
      return (y - this.y) / this.k;
    },
    rescaleX: function rescaleX(x) {
      return x.copy().domain(x.range().map(this.invertX, this).map(x.invert, x));
    },
    rescaleY: function rescaleY(y) {
      return y.copy().domain(y.range().map(this.invertY, this).map(y.invert, y));
    },
    toString: function toString() {
      return "translate(" + this.x + "," + this.y + ") scale(" + this.k + ")";
    }
  };
  var identity$9 = new Transform(1, 0, 0);
  transform$1.prototype = Transform.prototype;
  function transform$1(node) {
    return node.__zoom || identity$9;
  }

  function nopropagation$2() {
    exports.event.stopImmediatePropagation();
  }
  function noevent$2 () {
    exports.event.preventDefault();
    exports.event.stopImmediatePropagation();
  }

  function defaultFilter$2() {
    return !exports.event.button;
  }

  function defaultExtent$1() {
    var e = this,
        w,
        h;

    if (e instanceof SVGElement) {
      e = e.ownerSVGElement || e;
      w = e.width.baseVal.value;
      h = e.height.baseVal.value;
    } else {
      w = e.clientWidth;
      h = e.clientHeight;
    }

    return [[0, 0], [w, h]];
  }

  function defaultTransform() {
    return this.__zoom || identity$9;
  }

  function defaultWheelDelta() {
    return -exports.event.deltaY * (exports.event.deltaMode ? 120 : 1) / 500;
  }

  function defaultTouchable$1() {
    return "ontouchstart" in this;
  }

  function defaultConstrain(transform, extent, translateExtent) {
    var dx0 = transform.invertX(extent[0][0]) - translateExtent[0][0],
        dx1 = transform.invertX(extent[1][0]) - translateExtent[1][0],
        dy0 = transform.invertY(extent[0][1]) - translateExtent[0][1],
        dy1 = transform.invertY(extent[1][1]) - translateExtent[1][1];
    return transform.translate(dx1 > dx0 ? (dx0 + dx1) / 2 : Math.min(0, dx0) || Math.max(0, dx1), dy1 > dy0 ? (dy0 + dy1) / 2 : Math.min(0, dy0) || Math.max(0, dy1));
  }

  function zoom () {
    var filter = defaultFilter$2,
        extent = defaultExtent$1,
        constrain = defaultConstrain,
        wheelDelta = defaultWheelDelta,
        touchable = defaultTouchable$1,
        scaleExtent = [0, Infinity],
        translateExtent = [[-Infinity, -Infinity], [Infinity, Infinity]],
        duration = 250,
        interpolate = interpolateZoom,
        gestures = [],
        listeners = dispatch("start", "zoom", "end"),
        touchstarting,
        touchending,
        touchDelay = 500,
        wheelDelay = 150,
        clickDistance2 = 0;

    function zoom(selection$$1) {
      selection$$1.property("__zoom", defaultTransform).on("wheel.zoom", wheeled).on("mousedown.zoom", mousedowned).on("dblclick.zoom", dblclicked).filter(touchable).on("touchstart.zoom", touchstarted).on("touchmove.zoom", touchmoved).on("touchend.zoom touchcancel.zoom", touchended).style("touch-action", "none").style("-webkit-tap-highlight-color", "rgba(0,0,0,0)");
    }

    zoom.transform = function (collection, transform) {
      var selection$$1 = collection.selection ? collection.selection() : collection;
      selection$$1.property("__zoom", defaultTransform);

      if (collection !== selection$$1) {
        schedule(collection, transform);
      } else {
        selection$$1.interrupt().each(function () {
          gesture(this, arguments).start().zoom(null, typeof transform === "function" ? transform.apply(this, arguments) : transform).end();
        });
      }
    };

    zoom.scaleBy = function (selection$$1, k) {
      zoom.scaleTo(selection$$1, function () {
        var k0 = this.__zoom.k,
            k1 = typeof k === "function" ? k.apply(this, arguments) : k;
        return k0 * k1;
      });
    };

    zoom.scaleTo = function (selection$$1, k) {
      zoom.transform(selection$$1, function () {
        var e = extent.apply(this, arguments),
            t0 = this.__zoom,
            p0 = centroid(e),
            p1 = t0.invert(p0),
            k1 = typeof k === "function" ? k.apply(this, arguments) : k;
        return constrain(translate(scale(t0, k1), p0, p1), e, translateExtent);
      });
    };

    zoom.translateBy = function (selection$$1, x, y) {
      zoom.transform(selection$$1, function () {
        return constrain(this.__zoom.translate(typeof x === "function" ? x.apply(this, arguments) : x, typeof y === "function" ? y.apply(this, arguments) : y), extent.apply(this, arguments), translateExtent);
      });
    };

    zoom.translateTo = function (selection$$1, x, y) {
      zoom.transform(selection$$1, function () {
        var e = extent.apply(this, arguments),
            t = this.__zoom,
            p = centroid(e);
        return constrain(identity$9.translate(p[0], p[1]).scale(t.k).translate(typeof x === "function" ? -x.apply(this, arguments) : -x, typeof y === "function" ? -y.apply(this, arguments) : -y), e, translateExtent);
      });
    };

    function scale(transform, k) {
      k = Math.max(scaleExtent[0], Math.min(scaleExtent[1], k));
      return k === transform.k ? transform : new Transform(k, transform.x, transform.y);
    }

    function translate(transform, p0, p1) {
      var x = p0[0] - p1[0] * transform.k,
          y = p0[1] - p1[1] * transform.k;
      return x === transform.x && y === transform.y ? transform : new Transform(transform.k, x, y);
    }

    function centroid(extent) {
      return [(+extent[0][0] + +extent[1][0]) / 2, (+extent[0][1] + +extent[1][1]) / 2];
    }

    function schedule(transition$$1, transform, center) {
      transition$$1.on("start.zoom", function () {
        gesture(this, arguments).start();
      }).on("interrupt.zoom end.zoom", function () {
        gesture(this, arguments).end();
      }).tween("zoom", function () {
        var that = this,
            args = arguments,
            g = gesture(that, args),
            e = extent.apply(that, args),
            p = center || centroid(e),
            w = Math.max(e[1][0] - e[0][0], e[1][1] - e[0][1]),
            a = that.__zoom,
            b = typeof transform === "function" ? transform.apply(that, args) : transform,
            i = interpolate(a.invert(p).concat(w / a.k), b.invert(p).concat(w / b.k));
        return function (t) {
          if (t === 1) t = b; // Avoid rounding error on end.
          else {
              var l = i(t),
                  k = w / l[2];
              t = new Transform(k, p[0] - l[0] * k, p[1] - l[1] * k);
            }
          g.zoom(null, t);
        };
      });
    }

    function gesture(that, args) {
      for (var i = 0, n = gestures.length, g; i < n; ++i) {
        if ((g = gestures[i]).that === that) {
          return g;
        }
      }

      return new Gesture(that, args);
    }

    function Gesture(that, args) {
      this.that = that;
      this.args = args;
      this.index = -1;
      this.active = 0;
      this.extent = extent.apply(that, args);
    }

    Gesture.prototype = {
      start: function start() {
        if (++this.active === 1) {
          this.index = gestures.push(this) - 1;
          this.emit("start");
        }

        return this;
      },
      zoom: function zoom(key, transform) {
        if (this.mouse && key !== "mouse") this.mouse[1] = transform.invert(this.mouse[0]);
        if (this.touch0 && key !== "touch") this.touch0[1] = transform.invert(this.touch0[0]);
        if (this.touch1 && key !== "touch") this.touch1[1] = transform.invert(this.touch1[0]);
        this.that.__zoom = transform;
        this.emit("zoom");
        return this;
      },
      end: function end() {
        if (--this.active === 0) {
          gestures.splice(this.index, 1);
          this.index = -1;
          this.emit("end");
        }

        return this;
      },
      emit: function emit(type) {
        customEvent(new ZoomEvent(zoom, type, this.that.__zoom), listeners.apply, listeners, [type, this.that, this.args]);
      }
    };

    function wheeled() {
      if (!filter.apply(this, arguments)) return;
      var g = gesture(this, arguments),
          t = this.__zoom,
          k = Math.max(scaleExtent[0], Math.min(scaleExtent[1], t.k * Math.pow(2, wheelDelta.apply(this, arguments)))),
          p = mouse(this); // If the mouse is in the same location as before, reuse it.
      // If there were recent wheel events, reset the wheel idle timeout.

      if (g.wheel) {
        if (g.mouse[0][0] !== p[0] || g.mouse[0][1] !== p[1]) {
          g.mouse[1] = t.invert(g.mouse[0] = p);
        }

        clearTimeout(g.wheel);
      } // If this wheel event wonвЂ™t trigger a transform change, ignore it.
      else if (t.k === k) return; // Otherwise, capture the mouse point and location at the start.
        else {
            g.mouse = [p, t.invert(p)];
            interrupt(this);
            g.start();
          }

      noevent$2();
      g.wheel = setTimeout(wheelidled, wheelDelay);
      g.zoom("mouse", constrain(translate(scale(t, k), g.mouse[0], g.mouse[1]), g.extent, translateExtent));

      function wheelidled() {
        g.wheel = null;
        g.end();
      }
    }

    function mousedowned() {
      if (touchending || !filter.apply(this, arguments)) return;
      var g = gesture(this, arguments),
          v = select(exports.event.view).on("mousemove.zoom", mousemoved, true).on("mouseup.zoom", mouseupped, true),
          p = mouse(this),
          x0 = exports.event.clientX,
          y0 = exports.event.clientY;
      dragDisable(exports.event.view);
      nopropagation$2();
      g.mouse = [p, this.__zoom.invert(p)];
      interrupt(this);
      g.start();

      function mousemoved() {
        noevent$2();

        if (!g.moved) {
          var dx = exports.event.clientX - x0,
              dy = exports.event.clientY - y0;
          g.moved = dx * dx + dy * dy > clickDistance2;
        }

        g.zoom("mouse", constrain(translate(g.that.__zoom, g.mouse[0] = mouse(g.that), g.mouse[1]), g.extent, translateExtent));
      }

      function mouseupped() {
        v.on("mousemove.zoom mouseup.zoom", null);
        yesdrag(exports.event.view, g.moved);
        noevent$2();
        g.end();
      }
    }

    function dblclicked() {
      if (!filter.apply(this, arguments)) return;
      var t0 = this.__zoom,
          p0 = mouse(this),
          p1 = t0.invert(p0),
          k1 = t0.k * (exports.event.shiftKey ? 0.5 : 2),
          t1 = constrain(translate(scale(t0, k1), p0, p1), extent.apply(this, arguments), translateExtent);
      noevent$2();
      if (duration > 0) select(this).transition().duration(duration).call(schedule, t1, p0);else select(this).call(zoom.transform, t1);
    }

    function touchstarted() {
      if (!filter.apply(this, arguments)) return;
      var g = gesture(this, arguments),
          touches$$1 = exports.event.changedTouches,
          started,
          n = touches$$1.length,
          i,
          t,
          p;
      nopropagation$2();

      for (i = 0; i < n; ++i) {
        t = touches$$1[i], p = touch(this, touches$$1, t.identifier);
        p = [p, this.__zoom.invert(p), t.identifier];
        if (!g.touch0) g.touch0 = p, started = true;else if (!g.touch1) g.touch1 = p;
      } // If this is a dbltap, reroute to the (optional) dblclick.zoom handler.


      if (touchstarting) {
        touchstarting = clearTimeout(touchstarting);

        if (!g.touch1) {
          g.end();
          p = select(this).on("dblclick.zoom");
          if (p) p.apply(this, arguments);
          return;
        }
      }

      if (started) {
        touchstarting = setTimeout(function () {
          touchstarting = null;
        }, touchDelay);
        interrupt(this);
        g.start();
      }
    }

    function touchmoved() {
      var g = gesture(this, arguments),
          touches$$1 = exports.event.changedTouches,
          n = touches$$1.length,
          i,
          t,
          p,
          l;
      noevent$2();
      if (touchstarting) touchstarting = clearTimeout(touchstarting);

      for (i = 0; i < n; ++i) {
        t = touches$$1[i], p = touch(this, touches$$1, t.identifier);
        if (g.touch0 && g.touch0[2] === t.identifier) g.touch0[0] = p;else if (g.touch1 && g.touch1[2] === t.identifier) g.touch1[0] = p;
      }

      t = g.that.__zoom;

      if (g.touch1) {
        var p0 = g.touch0[0],
            l0 = g.touch0[1],
            p1 = g.touch1[0],
            l1 = g.touch1[1],
            dp = (dp = p1[0] - p0[0]) * dp + (dp = p1[1] - p0[1]) * dp,
            dl = (dl = l1[0] - l0[0]) * dl + (dl = l1[1] - l0[1]) * dl;
        t = scale(t, Math.sqrt(dp / dl));
        p = [(p0[0] + p1[0]) / 2, (p0[1] + p1[1]) / 2];
        l = [(l0[0] + l1[0]) / 2, (l0[1] + l1[1]) / 2];
      } else if (g.touch0) p = g.touch0[0], l = g.touch0[1];else return;

      g.zoom("touch", constrain(translate(t, p, l), g.extent, translateExtent));
    }

    function touchended() {
      var g = gesture(this, arguments),
          touches$$1 = exports.event.changedTouches,
          n = touches$$1.length,
          i,
          t;
      nopropagation$2();
      if (touchending) clearTimeout(touchending);
      touchending = setTimeout(function () {
        touchending = null;
      }, touchDelay);

      for (i = 0; i < n; ++i) {
        t = touches$$1[i];
        if (g.touch0 && g.touch0[2] === t.identifier) delete g.touch0;else if (g.touch1 && g.touch1[2] === t.identifier) delete g.touch1;
      }

      if (g.touch1 && !g.touch0) g.touch0 = g.touch1, delete g.touch1;
      if (g.touch0) g.touch0[1] = this.__zoom.invert(g.touch0[0]);else g.end();
    }

    zoom.wheelDelta = function (_) {
      return arguments.length ? (wheelDelta = typeof _ === "function" ? _ : constant$d(+_), zoom) : wheelDelta;
    };

    zoom.filter = function (_) {
      return arguments.length ? (filter = typeof _ === "function" ? _ : constant$d(!!_), zoom) : filter;
    };

    zoom.touchable = function (_) {
      return arguments.length ? (touchable = typeof _ === "function" ? _ : constant$d(!!_), zoom) : touchable;
    };

    zoom.extent = function (_) {
      return arguments.length ? (extent = typeof _ === "function" ? _ : constant$d([[+_[0][0], +_[0][1]], [+_[1][0], +_[1][1]]]), zoom) : extent;
    };

    zoom.scaleExtent = function (_) {
      return arguments.length ? (scaleExtent[0] = +_[0], scaleExtent[1] = +_[1], zoom) : [scaleExtent[0], scaleExtent[1]];
    };

    zoom.translateExtent = function (_) {
      return arguments.length ? (translateExtent[0][0] = +_[0][0], translateExtent[1][0] = +_[1][0], translateExtent[0][1] = +_[0][1], translateExtent[1][1] = +_[1][1], zoom) : [[translateExtent[0][0], translateExtent[0][1]], [translateExtent[1][0], translateExtent[1][1]]];
    };

    zoom.constrain = function (_) {
      return arguments.length ? (constrain = _, zoom) : constrain;
    };

    zoom.duration = function (_) {
      return arguments.length ? (duration = +_, zoom) : duration;
    };

    zoom.interpolate = function (_) {
      return arguments.length ? (interpolate = _, zoom) : interpolate;
    };

    zoom.on = function () {
      var value = listeners.on.apply(listeners, arguments);
      return value === listeners ? zoom : value;
    };

    zoom.clickDistance = function (_) {
      return arguments.length ? (clickDistance2 = (_ = +_) * _, zoom) : Math.sqrt(clickDistance2);
    };

    return zoom;
  }

  exports.version = version;
  exports.bisect = bisectRight;
  exports.bisectRight = bisectRight;
  exports.bisectLeft = bisectLeft;
  exports.ascending = ascending;
  exports.bisector = bisector;
  exports.cross = cross;
  exports.descending = descending;
  exports.deviation = deviation;
  exports.extent = extent;
  exports.histogram = histogram;
  exports.thresholdFreedmanDiaconis = freedmanDiaconis;
  exports.thresholdScott = scott;
  exports.thresholdSturges = thresholdSturges;
  exports.max = max;
  exports.mean = mean;
  exports.median = median;
  exports.merge = merge;
  exports.min = min;
  exports.pairs = pairs;
  exports.permute = permute;
  exports.quantile = threshold;
  exports.range = sequence;
  exports.scan = scan;
  exports.shuffle = shuffle;
  exports.sum = sum;
  exports.ticks = ticks;
  exports.tickIncrement = tickIncrement;
  exports.tickStep = tickStep;
  exports.transpose = transpose;
  exports.variance = variance;
  exports.zip = zip;
  exports.axisTop = axisTop;
  exports.axisRight = axisRight;
  exports.axisBottom = axisBottom;
  exports.axisLeft = axisLeft;
  exports.brush = brush;
  exports.brushX = brushX;
  exports.brushY = brushY;
  exports.brushSelection = brushSelection;
  exports.chord = chord;
  exports.ribbon = ribbon;
  exports.nest = nest;
  exports.set = set$2;
  exports.map = map$1;
  exports.keys = keys;
  exports.values = values;
  exports.entries = entries;
  exports.color = color;
  exports.rgb = rgb;
  exports.hsl = hsl;
  exports.lab = lab;
  exports.hcl = hcl;
  exports.lch = lch;
  exports.gray = gray;
  exports.cubehelix = cubehelix;
  exports.contours = contours;
  exports.contourDensity = density;
  exports.dispatch = dispatch;
  exports.drag = drag;
  exports.dragDisable = dragDisable;
  exports.dragEnable = yesdrag;
  exports.dsvFormat = dsvFormat;
  exports.csvParse = csvParse;
  exports.csvParseRows = csvParseRows;
  exports.csvFormat = csvFormat;
  exports.csvFormatBody = csvFormatBody;
  exports.csvFormatRows = csvFormatRows;
  exports.tsvParse = tsvParse;
  exports.tsvParseRows = tsvParseRows;
  exports.tsvFormat = tsvFormat;
  exports.tsvFormatBody = tsvFormatBody;
  exports.tsvFormatRows = tsvFormatRows;
  exports.autoType = autoType;
  exports.easeLinear = linear$1;
  exports.easeQuad = quadInOut;
  exports.easeQuadIn = quadIn;
  exports.easeQuadOut = quadOut;
  exports.easeQuadInOut = quadInOut;
  exports.easeCubic = cubicInOut;
  exports.easeCubicIn = cubicIn;
  exports.easeCubicOut = cubicOut;
  exports.easeCubicInOut = cubicInOut;
  exports.easePoly = polyInOut;
  exports.easePolyIn = polyIn;
  exports.easePolyOut = polyOut;
  exports.easePolyInOut = polyInOut;
  exports.easeSin = sinInOut;
  exports.easeSinIn = sinIn;
  exports.easeSinOut = sinOut;
  exports.easeSinInOut = sinInOut;
  exports.easeExp = expInOut;
  exports.easeExpIn = expIn;
  exports.easeExpOut = expOut;
  exports.easeExpInOut = expInOut;
  exports.easeCircle = circleInOut;
  exports.easeCircleIn = circleIn;
  exports.easeCircleOut = circleOut;
  exports.easeCircleInOut = circleInOut;
  exports.easeBounce = bounceOut;
  exports.easeBounceIn = bounceIn;
  exports.easeBounceOut = bounceOut;
  exports.easeBounceInOut = bounceInOut;
  exports.easeBack = backInOut;
  exports.easeBackIn = backIn;
  exports.easeBackOut = backOut;
  exports.easeBackInOut = backInOut;
  exports.easeElastic = elasticOut;
  exports.easeElasticIn = elasticIn;
  exports.easeElasticOut = elasticOut;
  exports.easeElasticInOut = elasticInOut;
  exports.blob = blob;
  exports.buffer = buffer;
  exports.dsv = dsv;
  exports.csv = csv$1;
  exports.tsv = tsv$1;
  exports.image = image;
  exports.json = json;
  exports.text = text;
  exports.xml = xml;
  exports.html = html;
  exports.svg = svg;
  exports.forceCenter = center$1;
  exports.forceCollide = collide;
  exports.forceLink = link;
  exports.forceManyBody = manyBody;
  exports.forceRadial = radial;
  exports.forceSimulation = simulation;
  exports.forceX = x$2;
  exports.forceY = y$2;
  exports.formatDefaultLocale = defaultLocale;
  exports.formatLocale = formatLocale;
  exports.formatSpecifier = formatSpecifier;
  exports.precisionFixed = precisionFixed;
  exports.precisionPrefix = precisionPrefix;
  exports.precisionRound = precisionRound;
  exports.geoArea = area$1;
  exports.geoBounds = bounds;
  exports.geoCentroid = centroid;
  exports.geoCircle = circle;
  exports.geoClipAntimeridian = clipAntimeridian;
  exports.geoClipCircle = clipCircle;
  exports.geoClipExtent = extent$1;
  exports.geoClipRectangle = clipRectangle;
  exports.geoContains = contains$1;
  exports.geoDistance = distance;
  exports.geoGraticule = graticule;
  exports.geoGraticule10 = graticule10;
  exports.geoInterpolate = interpolate$1;
  exports.geoLength = length$1;
  exports.geoPath = index$1;
  exports.geoAlbers = albers;
  exports.geoAlbersUsa = albersUsa;
  exports.geoAzimuthalEqualArea = azimuthalEqualArea;
  exports.geoAzimuthalEqualAreaRaw = azimuthalEqualAreaRaw;
  exports.geoAzimuthalEquidistant = azimuthalEquidistant;
  exports.geoAzimuthalEquidistantRaw = azimuthalEquidistantRaw;
  exports.geoConicConformal = conicConformal;
  exports.geoConicConformalRaw = conicConformalRaw;
  exports.geoConicEqualArea = conicEqualArea;
  exports.geoConicEqualAreaRaw = conicEqualAreaRaw;
  exports.geoConicEquidistant = conicEquidistant;
  exports.geoConicEquidistantRaw = conicEquidistantRaw;
  exports.geoEqualEarth = equalEarth;
  exports.geoEqualEarthRaw = equalEarthRaw;
  exports.geoEquirectangular = equirectangular;
  exports.geoEquirectangularRaw = equirectangularRaw;
  exports.geoGnomonic = gnomonic;
  exports.geoGnomonicRaw = gnomonicRaw;
  exports.geoIdentity = identity$5;
  exports.geoProjection = projection;
  exports.geoProjectionMutator = projectionMutator;
  exports.geoMercator = mercator;
  exports.geoMercatorRaw = mercatorRaw;
  exports.geoNaturalEarth1 = naturalEarth1;
  exports.geoNaturalEarth1Raw = naturalEarth1Raw;
  exports.geoOrthographic = orthographic;
  exports.geoOrthographicRaw = orthographicRaw;
  exports.geoStereographic = stereographic;
  exports.geoStereographicRaw = stereographicRaw;
  exports.geoTransverseMercator = transverseMercator;
  exports.geoTransverseMercatorRaw = transverseMercatorRaw;
  exports.geoRotation = rotation;
  exports.geoStream = geoStream;
  exports.geoTransform = transform;
  exports.cluster = cluster;
  exports.hierarchy = hierarchy;
  exports.pack = index$2;
  exports.packSiblings = siblings;
  exports.packEnclose = enclose;
  exports.partition = partition;
  exports.stratify = stratify;
  exports.tree = tree;
  exports.treemap = index$3;
  exports.treemapBinary = binary;
  exports.treemapDice = treemapDice;
  exports.treemapSlice = treemapSlice;
  exports.treemapSliceDice = sliceDice;
  exports.treemapSquarify = squarify;
  exports.treemapResquarify = resquarify;
  exports.interpolate = interpolateValue;
  exports.interpolateArray = array$1;
  exports.interpolateBasis = basis$1;
  exports.interpolateBasisClosed = basisClosed;
  exports.interpolateDate = date;
  exports.interpolateDiscrete = discrete;
  exports.interpolateHue = hue$1;
  exports.interpolateNumber = interpolateNumber;
  exports.interpolateObject = object;
  exports.interpolateRound = interpolateRound;
  exports.interpolateString = interpolateString;
  exports.interpolateTransformCss = interpolateTransformCss;
  exports.interpolateTransformSvg = interpolateTransformSvg;
  exports.interpolateZoom = interpolateZoom;
  exports.interpolateRgb = interpolateRgb;
  exports.interpolateRgbBasis = rgbBasis;
  exports.interpolateRgbBasisClosed = rgbBasisClosed;
  exports.interpolateHsl = hsl$2;
  exports.interpolateHslLong = hslLong;
  exports.interpolateLab = lab$1;
  exports.interpolateHcl = hcl$2;
  exports.interpolateHclLong = hclLong;
  exports.interpolateCubehelix = cubehelix$2;
  exports.interpolateCubehelixLong = cubehelixLong;
  exports.piecewise = piecewise;
  exports.quantize = quantize;
  exports.path = path;
  exports.polygonArea = area$2;
  exports.polygonCentroid = centroid$1;
  exports.polygonHull = hull;
  exports.polygonContains = contains$2;
  exports.polygonLength = length$2;
  exports.quadtree = quadtree;
  exports.randomUniform = uniform;
  exports.randomNormal = normal;
  exports.randomLogNormal = logNormal;
  exports.randomBates = bates;
  exports.randomIrwinHall = irwinHall;
  exports.randomExponential = exponential$1;
  exports.scaleBand = band;
  exports.scalePoint = point$1;
  exports.scaleIdentity = identity$7;
  exports.scaleLinear = linear$2;
  exports.scaleLog = log$1;
  exports.scaleSymlog = symlog;
  exports.scaleOrdinal = ordinal;
  exports.scaleImplicit = implicit;
  exports.scalePow = pow$1;
  exports.scaleSqrt = sqrt$1;
  exports.scaleQuantile = quantile$$1;
  exports.scaleQuantize = quantize$1;
  exports.scaleThreshold = threshold$1;
  exports.scaleTime = time;
  exports.scaleUtc = utcTime;
  exports.scaleSequential = sequential;
  exports.scaleSequentialLog = sequentialLog;
  exports.scaleSequentialPow = sequentialPow;
  exports.scaleSequentialSqrt = sequentialSqrt;
  exports.scaleSequentialSymlog = sequentialSymlog;
  exports.scaleSequentialQuantile = sequentialQuantile;
  exports.scaleDiverging = diverging;
  exports.scaleDivergingLog = divergingLog;
  exports.scaleDivergingPow = divergingPow;
  exports.scaleDivergingSqrt = divergingSqrt;
  exports.scaleDivergingSymlog = divergingSymlog;
  exports.tickFormat = tickFormat;
  exports.schemeCategory10 = category10;
  exports.schemeAccent = Accent;
  exports.schemeDark2 = Dark2;
  exports.schemePaired = Paired;
  exports.schemePastel1 = Pastel1;
  exports.schemePastel2 = Pastel2;
  exports.schemeSet1 = Set1;
  exports.schemeSet2 = Set2;
  exports.schemeSet3 = Set3;
  exports.interpolateBrBG = BrBG;
  exports.schemeBrBG = scheme;
  exports.interpolatePRGn = PRGn;
  exports.schemePRGn = scheme$1;
  exports.interpolatePiYG = PiYG;
  exports.schemePiYG = scheme$2;
  exports.interpolatePuOr = PuOr;
  exports.schemePuOr = scheme$3;
  exports.interpolateRdBu = RdBu;
  exports.schemeRdBu = scheme$4;
  exports.interpolateRdGy = RdGy;
  exports.schemeRdGy = scheme$5;
  exports.interpolateRdYlBu = RdYlBu;
  exports.schemeRdYlBu = scheme$6;
  exports.interpolateRdYlGn = RdYlGn;
  exports.schemeRdYlGn = scheme$7;
  exports.interpolateSpectral = Spectral;
  exports.schemeSpectral = scheme$8;
  exports.interpolateBuGn = BuGn;
  exports.schemeBuGn = scheme$9;
  exports.interpolateBuPu = BuPu;
  exports.schemeBuPu = scheme$a;
  exports.interpolateGnBu = GnBu;
  exports.schemeGnBu = scheme$b;
  exports.interpolateOrRd = OrRd;
  exports.schemeOrRd = scheme$c;
  exports.interpolatePuBuGn = PuBuGn;
  exports.schemePuBuGn = scheme$d;
  exports.interpolatePuBu = PuBu;
  exports.schemePuBu = scheme$e;
  exports.interpolatePuRd = PuRd;
  exports.schemePuRd = scheme$f;
  exports.interpolateRdPu = RdPu;
  exports.schemeRdPu = scheme$g;
  exports.interpolateYlGnBu = YlGnBu;
  exports.schemeYlGnBu = scheme$h;
  exports.interpolateYlGn = YlGn;
  exports.schemeYlGn = scheme$i;
  exports.interpolateYlOrBr = YlOrBr;
  exports.schemeYlOrBr = scheme$j;
  exports.interpolateYlOrRd = YlOrRd;
  exports.schemeYlOrRd = scheme$k;
  exports.interpolateBlues = Blues;
  exports.schemeBlues = scheme$l;
  exports.interpolateGreens = Greens;
  exports.schemeGreens = scheme$m;
  exports.interpolateGreys = Greys;
  exports.schemeGreys = scheme$n;
  exports.interpolatePurples = Purples;
  exports.schemePurples = scheme$o;
  exports.interpolateReds = Reds;
  exports.schemeReds = scheme$p;
  exports.interpolateOranges = Oranges;
  exports.schemeOranges = scheme$q;
  exports.interpolateCubehelixDefault = cubehelix$3;
  exports.interpolateRainbow = rainbow;
  exports.interpolateWarm = warm;
  exports.interpolateCool = cool;
  exports.interpolateSinebow = sinebow;
  exports.interpolateViridis = viridis;
  exports.interpolateMagma = magma;
  exports.interpolateInferno = inferno;
  exports.interpolatePlasma = plasma;
  exports.create = create;
  exports.creator = creator;
  exports.local = local;
  exports.matcher = matcher;
  exports.mouse = mouse;
  exports.namespace = namespace;
  exports.namespaces = namespaces;
  exports.clientPoint = point;
  exports.select = select;
  exports.selectAll = selectAll;
  exports.selection = selection;
  exports.selector = selector;
  exports.selectorAll = selectorAll;
  exports.style = styleValue;
  exports.touch = touch;
  exports.touches = touches;
  exports.window = defaultView;
  exports.customEvent = customEvent;
  exports.arc = arc;
  exports.area = area$3;
  exports.line = line;
  exports.pie = pie;
  exports.areaRadial = areaRadial;
  exports.radialArea = areaRadial;
  exports.lineRadial = lineRadial$1;
  exports.radialLine = lineRadial$1;
  exports.pointRadial = pointRadial;
  exports.linkHorizontal = linkHorizontal;
  exports.linkVertical = linkVertical;
  exports.linkRadial = linkRadial;
  exports.symbol = symbol;
  exports.symbols = symbols;
  exports.symbolCircle = circle$2;
  exports.symbolCross = cross$2;
  exports.symbolDiamond = diamond;
  exports.symbolSquare = square;
  exports.symbolStar = star;
  exports.symbolTriangle = triangle;
  exports.symbolWye = wye;
  exports.curveBasisClosed = basisClosed$1;
  exports.curveBasisOpen = basisOpen;
  exports.curveBasis = basis$2;
  exports.curveBundle = bundle;
  exports.curveCardinalClosed = cardinalClosed;
  exports.curveCardinalOpen = cardinalOpen;
  exports.curveCardinal = cardinal;
  exports.curveCatmullRomClosed = catmullRomClosed;
  exports.curveCatmullRomOpen = catmullRomOpen;
  exports.curveCatmullRom = catmullRom;
  exports.curveLinearClosed = linearClosed;
  exports.curveLinear = curveLinear;
  exports.curveMonotoneX = monotoneX;
  exports.curveMonotoneY = monotoneY;
  exports.curveNatural = natural;
  exports.curveStep = step;
  exports.curveStepAfter = stepAfter;
  exports.curveStepBefore = stepBefore;
  exports.stack = stack;
  exports.stackOffsetExpand = expand;
  exports.stackOffsetDiverging = diverging$1;
  exports.stackOffsetNone = none$1;
  exports.stackOffsetSilhouette = silhouette;
  exports.stackOffsetWiggle = wiggle;
  exports.stackOrderAppearance = appearance;
  exports.stackOrderAscending = ascending$3;
  exports.stackOrderDescending = descending$2;
  exports.stackOrderInsideOut = insideOut;
  exports.stackOrderNone = none$2;
  exports.stackOrderReverse = reverse;
  exports.timeInterval = newInterval;
  exports.timeMillisecond = millisecond;
  exports.timeMilliseconds = milliseconds;
  exports.utcMillisecond = millisecond;
  exports.utcMilliseconds = milliseconds;
  exports.timeSecond = second;
  exports.timeSeconds = seconds;
  exports.utcSecond = second;
  exports.utcSeconds = seconds;
  exports.timeMinute = minute;
  exports.timeMinutes = minutes;
  exports.timeHour = hour;
  exports.timeHours = hours;
  exports.timeDay = day;
  exports.timeDays = days;
  exports.timeWeek = sunday;
  exports.timeWeeks = sundays;
  exports.timeSunday = sunday;
  exports.timeSundays = sundays;
  exports.timeMonday = monday;
  exports.timeMondays = mondays;
  exports.timeTuesday = tuesday;
  exports.timeTuesdays = tuesdays;
  exports.timeWednesday = wednesday;
  exports.timeWednesdays = wednesdays;
  exports.timeThursday = thursday;
  exports.timeThursdays = thursdays;
  exports.timeFriday = friday;
  exports.timeFridays = fridays;
  exports.timeSaturday = saturday;
  exports.timeSaturdays = saturdays;
  exports.timeMonth = month;
  exports.timeMonths = months;
  exports.timeYear = year;
  exports.timeYears = years;
  exports.utcMinute = utcMinute;
  exports.utcMinutes = utcMinutes;
  exports.utcHour = utcHour;
  exports.utcHours = utcHours;
  exports.utcDay = utcDay;
  exports.utcDays = utcDays;
  exports.utcWeek = utcSunday;
  exports.utcWeeks = utcSundays;
  exports.utcSunday = utcSunday;
  exports.utcSundays = utcSundays;
  exports.utcMonday = utcMonday;
  exports.utcMondays = utcMondays;
  exports.utcTuesday = utcTuesday;
  exports.utcTuesdays = utcTuesdays;
  exports.utcWednesday = utcWednesday;
  exports.utcWednesdays = utcWednesdays;
  exports.utcThursday = utcThursday;
  exports.utcThursdays = utcThursdays;
  exports.utcFriday = utcFriday;
  exports.utcFridays = utcFridays;
  exports.utcSaturday = utcSaturday;
  exports.utcSaturdays = utcSaturdays;
  exports.utcMonth = utcMonth;
  exports.utcMonths = utcMonths;
  exports.utcYear = utcYear;
  exports.utcYears = utcYears;
  exports.timeFormatDefaultLocale = defaultLocale$1;
  exports.timeFormatLocale = formatLocale$1;
  exports.isoFormat = formatIso;
  exports.isoParse = parseIso;
  exports.now = now;
  exports.timer = timer;
  exports.timerFlush = timerFlush;
  exports.timeout = timeout$1;
  exports.interval = interval$1;
  exports.transition = transition;
  exports.active = active;
  exports.interrupt = interrupt;
  exports.voronoi = voronoi;
  exports.zoom = zoom;
  exports.zoomTransform = transform$1;
  exports.zoomIdentity = identity$9;

}((this.BX.Main = this.BX.Main || {})));
//# sourceMappingURL=d3js.bundle.js.map
